|SECOND GEOLOGICAL SURVEY OF PENNSYLVANIA - REPORT OF PROGRESS
P. DESCRIPTION OF THE COAL FLORA OF PENNSYLVANIA
AND OF THE
CARBONIFEROUS FORMATION THROUGHOUT THE UNITED STATES
BY LEO LESQUEREUX; ©1879
|Tables of Contents:
|All Four Volumes:
Scans and Webpage
©George Langford III, 2011
||NEUROPTERIS DILATATA||§2. NEPHROPTERIDS||Neuropteris Rogersi|
|NEUROPTERIDS||Cyclopteris dilatata||NEUROPTERIS FIMBRIATA||NEUROPTERIS GIBBOSA|
|NEUROPTERIS||Nephropteris dilatata||Cyclopteris fimbriata||Neuropteris Undans|
|§1. CYCLOPTERIDS.||NEUROPTERIS TRICHOMANOIDES||NEUROPTERIS DENTATA||N. gibbosa and N. undans|
|NEUROPTERIS RENIFORMIS||Cyclopteris trichomanoides||Cyclopteris undans||NEUROPTERIS AURICULATA|
|Cyclopteris reniformis||NEUROPTERIS LACINIATA||NEUROPTERIS ROGERSI||NEUROPTERIS INFLATA|
|Nephropteris reniformis||Cyclopteris laciniata||Neuropteris speciosa||Filicites conchocus|
The Lycopods, close relatives of the Ferns, hate been found also in formations of the same period. But their remains are of diminutive size, stems without leaves, like those of plants of an incipient race. It may be surmised, therefore, that the origin of the Ferns is older, and probably contemporaneous with the first traces of land vegetation.
This fact is also indicated by the preponderance of the Ferns in the coal measures, a preponderance clearly manifested by the considerable number of their species, and by the enormous size of the plants.
Atmospheric moisture and a high uniform degree of temperature, essentially contribute to the vegetation of the Ferns. These elements were at the highest, and it seems, equally distributed over our planet, during the carboniferous period. Hence the luxuriance of the Ferns which, at this epoch, covering the low grounds, have contributed at least one half of the materials of the coal.
From the Carboniferous to the present time, Ferns are recognized in every formation, but gradually less predominant. For however abundant they may have been in some circumstances, they have never since entered into the composition of the deposits of combustible minerals, coal, lignite, peat, in as remarkable a proportion as in the carboniferous times.
The number of species of coal Ferns cannot be positively ascertained now, on account of the difficulty of their identification from fragments generally too small, representing mere parts of fronds, which may differ only in some of their sub-divisions. Thus, parts of one and the same frond have been sometimes described under different specific or even generic names. Prof. W. P. Schimper, in his last work on vegetable Paleontology, records eight hundred and seventy species of coal Ferns, but supposes that from the uncertainty of the determinations, the real number may not be above six hundred.
Considering, however, that a fusion of two or more species into one may as easily result of the similarity of some of the fragments, as a multiplication of species from the diversity of others, and considering also that the study of the coal flora of this continent has greatly increased the materials relating to its history, especially by some new types, species, even groups of Ferns, I am inclined to believe that this beautiful family is represented in the Carboniferous by more than one thousand species.
This number still remains far below that of the Ferns living and known at the present time, when more than three thousand species are known. But a comparison between the old and present floras, tending to give an idea of their characters and of their riches, cannot be made without taking into consideration the physical circumstances of the globe at the different epochs. The flora of the coal is limited to certain classes of vegetables by the absence of numerous types unknown at that time in the vegetable kingdom, while the uniformity of the climate over the whole surface of the earth reduces the causative influences, or the modification of forms or characters, to a degree equivalent to what they may be now, within the area of a single low island of the Pacific ocean.
The number of species of Ferns in the Phillipine Islands is three hundred. Java and South Eastern Africa have about four hundred. Counting the species of the islands of the Gulf of Mexico and of the Eastern inter-tropical coast range, six to seven hundred are recorded. In all the countries above mentioned, the variations of the, climate, of the geological and geographical features, multiply ad infinitum the causes which may influence the vegetation and diversify the distribution of plants, to thus increase the number of species, even without taking into account the succession in the deviation of types resulting from the work of nature in space of time, or during the ages which separate the coal epoch front the present. It is evident that, considered on this point of view, the number of species of Ferns of. the coal, compared with that of our epoch, indicates for that .old formation a multiplicity, a diversity of vegetable forms of which the present flora cannot give an idea, even in the localities endowed with the most luxuriant vegetation.
It is upon the warm islands of the Pacific ocean and the Gulf of Mexico; also in the equatorial low region of Brazil, along the Amazon river, that this beautiful family of plants, attains now its greatest development. In these tropical regions, a comparatively large number of the Ferns becomes trees which sometimes reach to an altitude of one hundred feet. Rivaling the Palms by their shape, their port, they are superior to them by the elegance of their fronds and leaves, indefinitely cleaved into sub-divisions of exquisitely graceful and constantly varied patterns. Though high these trees may be, the diameter of the trunks, generally simple or without branches, and exactly cylindrical, is never considerable. It scarcely measures one foot. In this also the superiority of the vegetation of the Ferns at the coal epoch is evidenced, even in comparison with the present growth of these trees in the most favorable circumstances afforded by the climate ; for in the carboniferous measures of Ohio and Kentucky, silicified stems of Ferns have been found, measuring, in their perfectly cylindrical shape, more than two feet in diameter.
The Ferns belong to the highest order of the Cryptogams (the Acrogens), plants with a distinct axis, growing from the apex only, composed of woody fibres and vessels. They have that in common with the Equisetaceae; but they differ from them by the spiral development of their stems and branches, by their leaves, flat laminae, either entire or divided in multiple sections, according to the characters of their compound venation.
Concerning their growth, the Ferns are perennial, herbaceous, climbing, or arborescent. The fronds, before expansion, are involute in spiral, like a watch spring, and gradually unfold in the development of their stems and branches. ( Circinnate Vernation.)
As herbaceous, the Ferns grow in tufts from inflated rootstocks, ( rhizoma,) or come out successively from a more or less elongated creeping organ of the same kind. A large number of the species of the Carboniferous are bushy Ferns, many of them of very large size, known merely by fragments of stems or branches with leaves. Parts of fronds are seen sometimes on the roofs of the mines, measuring from three to four meters, and proportionally large, with flattened stalks, fifteen to twenty centimeters broad.
As arborescent, the stems of Ferns are erect, cylindrical, and woody; their fronds, then, open successively from the top, expanding umbrella-like, by the curving back of their petioles, sometimes very long. In separating from the stem, they leave upon the trunk deep, oval scars, preserved during the whole life of the trees. Atlas, Plate LIX and Plate LX.
Trunks of Ferns, mostly silicified, are plentifully found in the sandstone of the middle coal measures of Ohio and Kentucky. Their internal structure is distinctly preserved and may be studied by thin lamels, cut by the lapidary and polished appropriately for microscopical examination. In connection with the coal, the presence of tree Ferns is recognized, mostly in the roofing shale, by fragments of bark with scars of the petioles. Even impressions of scars are seen upon coal or coal shales without any remains of bark.
The rhizomas of bushy Ferns, generally of a soft, cellular, easily decomposed tissue, are rarely found petrified in the coal measures. Two species only, both American, are described by Schimper under the generic name of Rhizomopteris. They rather represent the bases of petioles than true rhizomas. A few remains of true root stalks, preserved in ferruginous concretions of Ill., are described in this volume.
The description of Ferns refers to the characters of their different parts as follows:
Fronds are the leaves of Ferns in their whole, including the stalks or petioles. They are either simple, without divisions of the axis; or branching, the branches (pinnae) being primary, when attached to the main axis; secondary, as divisions of a primary pinna, and so on, tertiary, quaternary, etc. Hence the fronds are simple, simply pinnate, bi, tri, polypinnate.
The divisions of the petiole (Rachis), answer to the same description as primary, secondary, tertiary, etc. These divisions of the fronds are more or less arbitrary for fossil Ferns mostly found in fragments of pinnae, whose fronds or primary divisions are often merely conjectural. The largest fragments of a compound pinna is generally considered as a primary pinna, often named leaf, and the description made accordingly.
For the description of Fern leaves or pinnules, sometimes named simple pinnae, the same terms are generally used as those applied to the dicotyledonous plants. They are entire or lobed, pinnate, bi, tri-pinnate, compound, multiple, etc.*
The more important characters in the determination of the Ferns are taken from the venation and the fructifications.
The vascular structure of Ferns is composed of cords or indurated vessels or tissues, termed scalariform, which branch from the base of the previous frond into the nascent bud of the forthcoming one, and lengthen upwards with the growth of the plant. It consists of two or more cylindrical, flat or channeled filaments or chords, which, on reaching the leafy part of the fronds, divide and ramify through all its parts. The ultimate ramifications ending in the leafy part (lamina), and called veins, either radiate from the base of fronds or segments in a flabellate manner, or more generally are produced from a midrib (costa), which, in simple fronds, is a continuation of the vascular cords of the stipes, or in segments of fronds, a branch of the rachis from which they are produced. **
Therefore two essential types of venation are marked in the Ferns of the coal. Either the leaves or leaflets are without midrib. Then all the veins come from their base, or from the point of union to the rachis, and pass up towards the borders in expanding fan-like by multiple, alternate, forkings (dichotomy). The venation is then flabellate and dichotomous. Or the leaves or leaflets have a midrib or costa, from which the veins are produced, passing towards the borders, either in right angle to the midrib, or in a more or less acute angle, simple or forking in divers ways, straight, curved or flexuous, etc. In their relation to the midrib they are called primary veins; their divisions secondary or venules; the branches of these veinlets. The veins are called forked when they divide in two branches; bifurcate in more than two; pinnate when the primary veins produce venules either alternate or opposite in regular order on both sides.
In living Ferns the leaves and pinnules of a number of species have an anastomosing venation, the apices of the branches of each proximate fascicle uniting with another and forming regular square, rhomboidal, or unequal-sided meshes. As yet this kind of venation has not been observed in any species of coal Ferns of this continent. The areolae or meshes of Dictyopteris are formed by undulations of the veins, not by anastomose.
The fructification of the living Ferns offers quite as valuable characters for their determination and classification as the venation.
The fruit-dots are generally placed upon the lower surface of the laminae or pinnules, in receptacles supporting or containing the ( sporanges), capsules which bear the (sori), glomerules of seeds. But the position of the sporanges, their form, the disposition of the sori, are rarely distinct enough upon fossil specimens to offer reliable points of observation. In some cases, and for silicified specimens only, the characters of the fruit-dots have been distinctly seen and described. As until now no deposits of silicified fragments of Ferns have been found in this continent, it would be an useless task to base the classification of the Ferns of the American coal measures upon characters which cannot be, or have not been studied here. Even in Europe, after the remarkable publications (the Systema and the Gattungen), where Goeppert attempted to expose the classification of the fossil Ferns from their fructification, this system has been generally abandoned.
It is therefore upon the characters clearly seen, those taken from the distribution of the pinnae and of their branches; from the forms and sub-divisions of the pinnules or leaflets, and especially from the venation, that the descriptions of the fossil Ferns are made.
Brongniart has proposed a simple and clear classification based on those characters. Though some carboniferous types may not find an appropriate place in it, it has been and is still now generally followed. It was given first in Histoire des Vegetaux fossiles 1828-1837, and later somewhat modified in Tableaux des Genres des Vegetaux fossiles, 1849. Schimper's lucid and abridged exposition of the system is as follows: *
1. Frond simple or with compound pinnules, free or adhering without midrib, or with a midrib appearing near the base, but vanishing upwards; veins dichotomous, flabellate. (Neuropterideae.)
2. Frond bi- tri-pinnate, with pinnae or pinnules narrowed to the base, flabelliform, entire or scarcely lobed; veins diverging from the base without a more distinct midrib. ( Adiantideae.)
3. Fronds like the former ones, diversely lobed; veins pinnate or bi-pinnate from the base; secondary divisions very oblique. ( Sphenopterideae.)
4. Fronds simple, pinnate or bi-tri-pinnatifid, with pinnules generally adhering by their base to the rachis, often confluent, forming only more or less deep lobes, entire or denticulate, not lobed; secondary veins pinnate or dichotomous. ( Pecopterideae.)
Another classification applied to living and fossil Ferns, and based also upon the venation, has been proposed by d'Ettingshausen in a work illustrated by physiotypical plates of great excellence. The divisions of the Ferns, as established by this author, are very numerous and cannot be easily understood without the illustrations. Schimper has also given a synopsis of this system, Paleont. p. 365, etc.
I have therefore, in this work, followed Brongniart's classification, with some changes in accordance to the characters of the plants which have to be described.
The first section is limited as indicated above by Brongniart; the second section is that of the Alethopterids allied to the Neuropterids by their nervation but evidently different by the fructifications.
The Pecopterids are left as described by Brongniart for the third section; and I admit to the Sphenopterids as a mere sub-division of this family, the Adiantides, especially represented by Archaeopteris.
Neuropteris, Lesleya, Dictyopteris and Odontopteris,
are the only ones which I refer to this section. They represent a very
distinct, most interesting group of the Ferns of the coal, all bushy
plants of great size, with broad rachis, pinnae and pinnules of the
most beautiful forms. Science has vainly searched for an analogy of
these Ferns to some of those living at this time. No species of this
group has passed above the Permian.
The first Genus admitted and described by Brongniart, in this section, Cyclopteris, was established for leaflets of great size, generally orbicular, as indicated by the name, related to Neuropteris by their venation, but which always found isolated, could not be positively referred to the original plants wherefrom they had been derived. To these the author added two species—Cyclopteris digitata and Cyclopteris flabellata, which, related to the Jurassic types Baiera or Salisburia, do not find place with the Ferns. Of this kind are the Whittleseya, or allied types, represented in Atlas, Plate IV, f. 1-3.
By and by the true identity of the species of Cyclopteris (Neuropterids) which, later, Brongniart separated in his Tableau de Genres, under the name of Nephropteris, have been more or less positively identified as true Neuropteris, species which bear upon the same pinnae, and according to the position which they occupy, some leaflets with a flabellate dichotomous venation, without any midrib (Nephropteris), and others with a distinct middle nerve, from which the veins curve in diverging and anastomosing toward the borders, true Neuropteris.
As this genus is widely represented in the North American coal measures, not merely by species whose characters are definite and often peculiar, but also by a prodigious number of specimens, sometimes filling whole layers of shale, it has been possible to follow the multiple variations of these plants, and to refer to their original types, separate leaflets which, seen isolated in collections, may be easily, and have been often, considered as representing different species. In the final report of the Geol. of Penn'a, 1858, I had already figured part of a pinna of Neuropteris hirsuta, Pl. III, f. 6, showing the relative position of large terminal pinnules marked with a distinct costa, to small basilar ones, leaflets with the characters of true Cyclopteris, without trace of medial nerves, all the veins being dichotomous and flabellate from the more or less enlarging base. In the same work are represented also, Pl. IV, f. 1-16, the extremely variable forms of the pinnules of the same species which could be identified by the hairs of the surface. Since then, in pursuing researches in the same direction, I have had opportunity to recognize the relation of the large leaflets, Cyclopteris, to different species of Neuropteris, either by immediate attachment upon the rachis of pinnae, bearing both the neuropterid and the cyclopterid leaflets, as in Neuropteris rarinervis; or by evidence of some characters peculiar to both kinds of pinnules, as in those of Neuropteris fimbriata, Neuropteris undans, etc. Therefore, both genera Cyclopteris and Nephropteris are eliminated from this group.
Other devonian Ferns, described as Cyclopteris, by Geoppert, Unger, and Dawson, have been referred to Archaeopteris, Adiantites, Aneimites, Triphyllopteris, and other divisions which have no relation to the Neuropterids. Two species of Goeppert, Cyclopteris polymorpha and Cyclopteris frondosa, are separated by Schimper under the name of Cardiopteris, as intermediate to Neuropteris and Odontopteris. This type has not been recognized as yet in the fossil flora of this continent.
Fronds simply, bi, tri-pinnate; pinnules varying from round to ovate,
obtuse, or obtusely acuminate, mostly entire, rounded, cordate, or
auricled at the base, attached to the rachis by the middle; sessile, or
rarely short pedicelled; veins either from the base of the pinnules or
from a costa, diverging fanlike and arched backwards, in passing
towards the borders, many times dichotomous; costa generally dissolved
at or below the middle; basilar veins simple or in fascicles.
The question concerning the characters of the fructifications of Neuropteris is still undecided, and demands some consideration.
Brongniart, Hist. d. Veg. foss., has represented a leaflet of Neuropteris flexuosa, Pl. 65, f. 3a, bearing at the forking of the veins, between their branches, in the proximity of the mid-rib, small, oblong, obtuse tubercles, resembling sporanges, which he considered as fructifications of this species. Later, recognizing the same kind of organism upon a specimen of Pecopteris Defrancii, preserved in the museum of Strasburg, he abandoned his first opinion, from the fact that, upon some of the pinnules, these small excrescences did cover the whole surface, while in others, few only were seen between some of the veins, and others still had none at all. He further remarks, that their reparation had no regularity, like the fructifications of Ferns, and that he has seen alterations of the parenchym, by parasite Cryptogams, upon living Ferns of different genera, Polypodium, Aspidium, Pteris, etc., presenting the same appearance. These organisms have been observed often since by phytopaleontologists. I figured them already in Geol. of Penn'a, 1858, Pl. V, f. 3, attached to the leaflets of Neuropteris gibbosa, remarking, p. 858, that there were near the midrib, between the veins, and exactly following their directions, some short narrow depressions which, by their form and symmetry did appear of an organic nature; but that it was not possible to ascertain if they were truly the fructifications of these plants. Since then, I have found them always of the same form, in the same position, in one, two, or more rows, near the costa, at the forks of the veins, between two branches, and following their direction, therefore more or less oblique to the mid-rib. They are, as described above, mammillate or inflated, sometimes, when in a mature state, apparently concave, the oval small, cavities appearing as bordered by a narrow rim; mostly all of the same size, about one millimeter long and half as broad. A number of specimens of Neuropteris Clarksoni, Neuropteris hirsuta, Neuropteris Loschii, etc., in the cabinet of Mr. Lacoe, of Pittston, abundantly bear those small mammillae upon the leaflets.
Professor Heer has observed upon the under side of the pinnules of Neuropteris flexuosa, another kind of tubercles, placed in two regular rows, following the directions of the veins, oblique to the midrib, and in the middle of the space between the costa and the borders. From their regular position, he considers them as fructifications, and as different from those which he has seen also upon the same species, and which he says are always irregularly placed, and of the same character as those described by Brongniart. I do not put into question the reality of the observation of my celebrated friend. I must say, however, that upon many specimens I have seen those tubercles not merely at a distance from the midrib, but generally in a regular order of distribution, following always the direction of the veins, and of course either nearly parallel to the costa, or in various angles, according to their distance from it, even nearly at right angles when placed between veins very curved, and toward the middle of the laminae.
On another side, the observations of Brongniart on the likeness of small parasite plants seen upon living species of Ferns and similar to those of the Neuropterids is correct. I have seen these parasite, species of Hysterium, also upon the leaves of Salisburia. But in these as upon living Ferns, the tubercles though generally placed between the veins and parallel to them, are sometimes across or traversing them in right angle, a position that I have never observed upon the supposed sporanges of Neuropteris.
The fact of these being true sporanges is confirmed in some degree by the discovery of the fructifications of Odontopteris by Grand'Eury, described, Fl. Carb., Pl. XIII, f. 4. The sporanges are about of the same form as those of Neuropteris but borne upon the point of the veins or of their branches on the border of the leaves. It may be, therefore, that the fructifications of Neuropteris are sporanges, always placed between the veins, either irregularly scattered in the middle of the leaflets or in some cases disposed in one or two regular rows as seen by Prof. Heer.
These remarks show the insufficiency of the characters offered by the fructifications for the determination of fossil Ferns. The observations of Brongniart have been published in 1828, and since then, or for half a century, paleontologists pursuing their investigations into the nature of the remarkable group of the Neuropterids, have not been able even to positively ascertain if the tubercles so rarely observed upon the leaflets are mere parasite protuberances or true sporanges. With few exceptions the veins of the Neuropterids are distinct, and their position, carefully compared, especially their number as counted in a given space along the borders, ought to be mostly taken in account in the specification of their fossil fragments.
From their relative affinities the species of Neuropteris are grouped in four sections: Cyclopterids, Nephropterids, Euneuropterids, Pachydermate and Anomalous Neuropterids.
NEUROPTERIS RENIFORMIS ? Brgt., Plate IV, f. 5.Leaflets symmetrical, round, entire, slightly undulate on the borders, deeply indented at the point of insertion; veins distinct from the base, diverging fan-like, arched, dichotomous and distant.
Cyclopteris reniformis, Brgt., Hist. d. Veg. Foss., p. 216, Pl. 61, bis, f. 1.
Nephropteris reniformis, Schp., Paleont. Veget., 1, p. 430.
Except the characters of venation, little is known of this species described by the author from mere fragments. His figure represents only the lower part of a leaflet, precisely the part which has been half destroyed upon our specimen. It merely shows identity in the form of the pinnule. But in the European species, the veins, simple at the base and divided in outside branches, are rather pedate than dichotomous, and this character is not distinctly observable upon our fragment. The American form differs from Cyclopteris orbicularis, Brgt., which I consider as identical to Neuropteris rarinervis, by its thick coriaceous texture and smooth surface. The veins are thin or divided in two or three parallel vascular filaments, deeply immersed into the parenchima which thus upraised in the intervals, takes the appearance of very thick obtuse veins. The distance of the veins along the border is three fourths of a millimeter. It is not possible to distinctly see upon our specimen if the base of the leaflet is auriculate. It appears as if the fragment of stem closing the notch was pressed upon the border of the lamina, either casually joined to the leaflet, or perhaps a fragment of rachis to which it was attached.
Habitat—The two only leaves known of this Fern were found in a lot of specimens sent for determination by Prof. E. A. Smith, of Tuscaloosa, Ala. One of them, indicating the outlines of the leaves, is figured; the other is very fragmentary. The specimens have no labels. The color and consistence of the matter, a gray soft shale, are the same as in other fragments obtained from Helena mines, Ala. As I have never seen the species in the middle coal measures, its origin in the sub-carboniferous coal of Alabama is more than probable.
NEUROPTERIS DILATATA, Ll. & Hutt.Leaflets very large, transversely oval; texture thin; veins distant, dichotomous, diverging fanlike.
Cyclopteris dilatata, Ll. & Hutt., Foss. fl., II, Pl. 91. B.
Nephropteris dilatata, Schp., Pal. Veget., 1, p. 430.
This species is as yet represented in our flora by two splendid specimens, leaflets, one measuring fourteen centimeters transversely, and seven in vertical line; the other, twenty-two centimeters by eleven. The base is expanded in large auricles, passing around the circular point of insertion and overlapping each other. In the largest leaf, the overlapping borders are erased, but they are still two and a half centimeters broad where they join each other under the point of attachment. The borders are undulate; the veins fifteen millimeters apart, or twice as distant as in the former species, irregularly inflated, sometimes split into two parallel fascicles, rarely in simple thread-like filaments. These leaflets clearly represent the English species distinguishable from the former as from any congener by the large size, the lateral widening, the thin substance of the lamina, and the distant veins. I have been unable as yet to recognize these characters in any other of the American Neuropterids.
Habitat—Clinton, Mo. Lower coal measures. Communicated by Dr. John H. Britts.
NEUROPTERIS TRICHOMANOIDES, Brgt., Plate IV, Fig. 4.Leaflets nearly round and equilateral, deeply notched at the point of attachment, entire or undulate; reins thin, dichotomous, flabellate, nearly straight or slightly arched in passing to the borders, where they become very close.
Cyclopteris trichomanoides, Brgt., Hist. d. Veg. foss., p. 217, Pl. LXI, bis. f. 4.
Lesqx., Geol. of Penn'a, 1858, p. 856.
Schp., Paleont. Veget., 1, p. 421.
Heer, Fl. foss. Helv., IV, p. 17, Pl. VI, f. 16.
I have figured the largest of the leaflets referred to this species. It is somewhat more enlarged on one side than on the other. A number of others from the same locality are precisely equilateral, with borders slightly undulate, as in the specimen figured by Brongniart. The thin veins are free to the base, not fasciculate, close, especially so, near the borders, where they become scarcely distinct to the naked eye, there numbering forty to fifty per centimeter.
These large leaflets are not rare at Cannelton, where also are found separate neuropterid pinnules and fragments of pinnae of a species which I have referred to Neuropteris capitata, Atlas, Plate XXIII, f. 2, 3. The venation of all these specimens is of the same character. The fragment, Plate XXIII, f. 1, is from Illinois. It differs by the veins slightly more distant, though quite as thin. No cyclopterid pinnules have been found in connection with it. It is, therefore, possible that the Cannelton plants, both the small and large leaflets, may represent a new species, though they have as characters the same peculiar enlargement of the terminal pinnules indicated by the specific name. On another side, the specimens referred to this species in Geol. of Penn'a, 1858, have the same character of venation as those of Cannelton, but the fragments of Neuropteris, seen at the same locality, represent mostly Neuropteris cordata, or Neuropteris angustifolia, Brgt. The identification of the American specimens with the species of Brongniart is, therefore, doubtful. It is based only on the similarity of shape and size of the leaflets, and on the same distribution of the veins, which, according to the remarks of the author, are thin and very close on the borders.
Habitat --Gate Vein, near Pottsville. Not rare in the shale at the base of the bed of Cannel coal, at Cannelton, Pa.
NEUROPTERIS LACINIATA, Lesqx.Leaflets thick, quadrato-orbicular, cordate; borders fringed, from below the middle upwards, by long, flexuous, thread like, acuminate divisions; veins dichotomous, flabellate, very close, nearly straight.
Cyclopteris laciniata, Lesqx., Geol. of Penn'a, 1858, p. 855, Pl. XIX, f. 3, Boston Jour. S. N. H., Vol. VI, p. 416.
By its nervation, the leaflet is related to the following species, but it greatly differs by its thick texture and the scaly surface obliterating the nervation which is seen only when the epidermis is destroyed. The fimbriate divisions of the borders are also much closer and thinner. It seems to represent the cyclopterid form of Odontopteris squamosa, found at the same locality, whose venation and thick epidermis are of the same characters. This last species however has the leaflets entire. But the upper pinnae of Neuropteris fimbriata presents the same difference, the large leaflets only being fringed.
Habitat—Muddy Creek vein, between Pottsville and Tremont, Pa.
NEUROPTERIS FIMBRIATA, Lesqx., Plate V, Figs. 1-6.Fronds bi-tripinnately divided; primary pinnae apparently large, triangular in outline secondary divisions linear, slightly oblique; pinnules alternate, oval or oblong, obtuse, rarely entire, generally fringed from the middle upwards, distant, attached to the rachis by a broad base, the upper ones slightly decurring; veins distinct, flabellate and dichotomous from the base; rachis finely equally striate, more or less punctate.
Geol. Rept. of Ill., II, p. 430; IV, p. 384, Pl. VI., f. 4.
Schp., Paleont., Veget., III, p. 474.
Cyclopteris fimbriata, Lesqx., Boston Journ., S. N. H., Vol. VI, p. 416; Geol. of Penn'a, 1858, p. 855, Pl. IV, f. 17, 18.
The first specimens found of this species are the large cyclopterid leaflets figured, Geol. of Penn'a., 1858, l.c., one of which Plate V, f. 6 is copied. Later, this species was found in Illinois in numerous specimens, representing its various characters. A part of a pinna with smaller leaflets attached to a flexuous rachis, Plate V, f. 3, was described in both the Repts. of Ill., Vol. II and IV. Others of cyclopterid form like Plate V, f. 2, show the mode of distribution of the leaflets upon the rachis; a third, Plate V, f. 1, is a pinna with small pinnules mostly entire, some of them, as seen on the right part of the figure, having the top already slightly laciniate, while Plate V, f. 4 and 5 represent detached and isolated pinnules of the same characters. We can thus follow the divers forms of the leaves in their connection with the upper pinnae, or with the lower branches. They preserve the same characters, the shape only being modified in the cordate base, as in Plate V, f. 4 and 5, without any variation in their venation. The texture is not thick, rather delicate, the veins always distinct, forking generally twice, in the small leaflets, Plate V, f. 1; far more distant and distinct than in Neuropteris Loschii, Brgt.; even more distinct than in Neuropteris tenuifolia, Brgt., both species to which the upper branches with small pinnules are comparable by their size and shape.
Prof. Heer considered the first specimens of this fine species as perhaps representing fruiting pinnules of some Cyclopteris, or as having had the border casually lacerated by maceration and compression. But later he obtained from the anthracite of Switzerland a species, Cyclopteris lacerata, with leaflets laciniate like ours by a natural subdivision of the borders, differing, however, by a more dense nervation.
Habitat—Salem vein (upper coal measures); Pottsville, New Philadelphia, Pa. I have seen it in private collections at Charleston, Va., and abundantly in nodules procured from Ohio, in the cabinet of Dr. Hildreth, of Marietta. The geological station of these last specimens is unknown to me. As the species is not rare in the low coal of Morris, Ills., and in the nodules of Mazon Creek; as it is present, also, at Cannelton, and indeed in most of the collections which I have examined, it appears generally distributed in the middle coal measures, from the Conglomerate upwards, as far up as the Salem vein. It has not been found, as yet, in the sub-carboniferous measures.
NEUROPTERIS DENTATA, Lesqx., Plate V, Figs. 7, 8.Pinnules ovate, obtuse, truncate or subcordate at the base, irregularly lacerate-dentate, and lobed in the upper part; veins dichotomous, flabellate, slightly arched in passing to the border, thin, close.
Boston Journ., S. N. H., Vol. VI, p. 418.
Geol. of Penn'a, 1858, p. 859, Pl. V, f. 9 and 10.
Schp., Paleont. Vega., I, P. 447.
Cyclopteris undans, Lesqx., Ibid., p. 855, Pl. IV, f. 21, 22.
We have still here the neuropterid and cyclopterid forms of a species which is extremely rare in our coal measures. The outline of the pinnules is about the same as in Neuropteris fimbriata; but the venation is quite different, the veins being thin, close, slightly arched; and the texture of the pinnules thick, hard, and rigid. No remains of rachis have been found in connection with these leaflets, though the three pinnules on the left of Plate V, f. 7 appear to be, or to have been attached to a rachis (destroyed). I considered at first the large pinnules as different, and from their close, rigid venation supposed them to be cyclopterid form of Neuropteris undans. They differ, however, by more distinct, veins, and by the dentate borders. By the nervation, this species is allied to Cyclopteris ciliata, Heer, Fl. foss. Helv. IV, p. 17, Pl. VI, f. 24, in the same degree of affinity that Neuropteris fimbriata is to Cyclopteris lacerata of the same author.
Habitat—Blakely and Gate veins, near Pottsville, Pa.
NEUROPTERIS ROGERSI, Lesqx., Plate VI, Figs. 7-10.Pinnae or pinnules large, oval, or ovate-lanceolate, obtuse, or obtusely pointed, even slightly cuspidate, deeply cordate or distinctly auricled, entire; veins dichotomous from the base or from a thin middle vein, flabellate, slightly arched, very distinct, turning upwards in reaching the borders.
Neuropteris speciosa, Lesqx., Boston Journ., S. N. H., Vol. VI, p. 417.
Neuropteris Rogersi,* Lesqx., Geol. of Penn'a, 1858, p.856, Pl. VII, f. 2.
Schp., Paleont. Veget. I, p. 445.
The pinnules vary in size from four and a half to fourteen centimeters long, and from three to six centimeters broad, below the middle, where they are the widest. Some of them, like Plate VI, f. 7, are oblong-lanceolate, comparatively narrow; others, like Plate VI, f. 9 and 10, are much shorter, comparatively broad, nearly oval, generally with a symmetrical base, but sothetimes with one side slightly more enlarged and prolonged downward. This character seen, Plate VI, f. 9, indicates that these pinnules are not simple, but were originally attached to a common rachis, though all have been found isolated. The nervation is rather. neuropterid, as generally the pinnules have a narrow costa, not thicker than the lateral veins, appearing like a continuation of them. But in some specimens, in the small leaflets especially, the veins are all flabellate from the base.
This species is not comparable to any of the congeners. From Neuropteris hirsuta and Neuropteris angustifolia, both species very variable in the form of the leaflets, it differs by the more distant equal, sharp veins, not inflated or fasciculate toward the base, abruptly turned up along the borders, and equi-distant in their whole length; by the thin substance of the leaflets, their smooth shining surface and the deeply cordate auricled base, always marked by a comparatively small circular point of attachment. It is one of the most beautiful and most rare of the American species of Neuropteris.
Habitat—South Salem vein, behind Port Carbon, Pa., found in roof shale from an abandoned shaft, just north of the village, and also opposite on the other side of the creek in the same vein, from a thin bed of coal which was still worked in 1868. The pinnules are rarely orbicular. I found only one of this shape and even not distinct enough to positively show specific identity. Recently, 1879, two specimens of this species have been sent from Cannelton, Pa., by Mr. I. F. Mansfield.
NEUROPTERIS GIBBOSA, Lesqx., Plate VI, Figs. 1-6.Pinnae large, linear-lanceolate; pinnules oblique, subalternate, lanceolate or oblong, obtuse, cordate or truncate at base, more or less deeply undulate on the borders; veins flabellate from the enlarged base, very thin, many times dichotomous.
Boston Jour. S. N. H., Vol. VI, p. 418.
Geol. of Penn'a, 1858, p. 858, Pl. V, f. 3.
Neuropteris Undans, Lesqx., Boston Jour. S. N. H., Vol. VI, p. 418.
Geol. of Penn'a, 1858, p. 859, Pl. V, f. 1-2.
Neuropteris gibbosa and Neuropteris undans, Schp., Paleont. Veget., 1, p. 446.
From the examination of numerous specimens referable either to Neuropteris undans or to Neuropteris gibbosa, I now believe that they all represent the same species. The separation could be made merely from the surface of the pinnules, shining or smooth in Neuropteris gibbosa, dull or dusky black in Neuropteris undans. I generally found the veins in this last form more inflated towards the base even fasciculate. But these differences are of too little specific value. The terminal pinnules, large and undulate, represented, Geol. of Penna., 1858, Pl. V., f. 1-2, have not been observed in any other specimens. They seem however reproduced on a reduced scale in f. 4 and 5 of Plate VI, small upper pinnae of the same species. The lateral pinnules are not distinctly undulate and the terminal ones not as large. They have all the same kind of venation. The round leaflet is evidently attached to the broken base of a pinna bearing the lateral pinnules in the upper part of the specimen. Plate VI, f. 6 is the cyclopterid form of the same species with characters of nervation similar to those of f. 20, Pl. IV, of the Geol. of Penna., 1858. Its analogy is with Neuropteris auriculata, Brgt., from which it especially differs by the longer, lanceolate, narrower and equal leaflets.
Habitat—Upper Anthracite Coal measures, Gate and Salem veins, near Pottsville, Pa. I have received also the cyclopterid form from Cannelton, one specimen only.
NEUROPTERIS AURICULATA ? Brgt., Plate VI; Fig. 11.Frond large, bi-pinnate; pinnules open, round, reniform or oval, sessile, and attached by a large base, cordate or auriculate, with borders undulate or sinuate; costa merely basilar or none; veins diverging from the base, very thin and close.
Brgt., Hist. d. Veget. foss., p. 236, Pl. LXVI.
Germ., Verst., p. 9, Pl. IV.
Schp., Paleont. Veget., I, p. 443.
I am unable to ascertain if the fragment figured here, represents the European species. I have, as yet, not seen any other specimen of the American coal flora which could be positively referred to Neuropteris auriculata. This fragment does not show the characters of the middle pinnae represented by Brongniart; but Germar, who has described this species also, and given a fine illustration of it, l.c., has, in f. 2, the upper part of a pinna, with two lateral leaflets and a terminal one so perfectly according in character with the fragment figured here, that it would not be possible to doubt identity, if the veins were somewhat more curved in our specimen. This species, if truly American, is extremely rare in our coal measures.
Schimper rightly refers Neuropteris Villersii, Brgt., to this species. The plant described under this last name in Geol. of Penn'a, 1858, p. 858, Pl. III, f. 3, has its leaflets of a different size on each side of the pinnae, in the same way as in the figure given by the author, but the lateral veins are more distant, stronger, and not as curved. It is probably referable to Neuropteris callosa.
Habitat—Cannelton, Pa., Mr. I. F. Mansfield.
NEUROPTERIS INFLATA, Lesqx., Plate VII, Fig. 2-4a.Bi-pinnate; rachis thick, irregularly striate; pinnae linear; pinnules alternate or sub-opposite, oval, obtuse, rounded to the base, sessile; veins flabellate and inflated from the base, dichotomous, curved, thin and close along the borders; upper surface convex.
Geol. Rept. of Ill., II, p. 431, Pl. XXXVII, f. 2.
Schp., Paleont. Veget., III, P. 475.
Filicites conchocus? Germ. & Kaulf., Abdr., p. 227, Pl. LXVI, f. 5.
Comparing the fragment of pinna, Plate VII, f. 4, with that Plate VII, f. 2, it is at first difficult to admit them as representing the same species. The peculiar form of the oval leaflets, rounded to an enlarged point of attachment, slightly enlarged at the inferior basilar rounded corner; the nervation, veins inflated, and. thus apparently thick towards the base, becoming very thin and close along the borders, where they count 25-30 per centimeter; the convex surface, the distant pinnules, slightly oblique, and the comparatively broad rachis, all present the same character. The thick rachis of the large pinna, Plate VII, f. 2, ascends high up into the terminal leaflet. The second pinnule in descending preserves still an acuminate fragment of the rachis, but except this, the venation is exactly cyclopterid. The difference in the size of the pinnules is very great. The large ones, Plate VII, f. 3, are four and a half centimeters long, and as broad, while those of the pinna, PlateVII, f. 4, are only fifteen millimeters long, and six broad. A difference quite as marked is seen in other species of Neuropteris; e. g. Clarksoni, etc., and indeed it is often a difficult task to ascertain the identity of the pinnules of the upper pinnae with those of the lower ones.
Filicites conchaceus , Germ. & Kaulf., shows by the figure and the remarks of the authors, a great affinity to this species. In the description, they compared the pinnule to a flattened Pectinite or shell, and mention the veins as close from the middle upwards, and very thin along the borders. The two opposite leaflets figured in the Geol. Rept. of Ill., l.c., present the same appearance as also the one Plate VII, f. 3, of our plate. But the fragment of a single leaflet, which the German authors had for examination, is too imperfect; even the borders are erased in the whole circumference, and the description of the venation is incomplete. From it, the pinnule may be referred quite as well to Neuropteris Germari.
Habitat.—All the specimens seen from this species, representing large leaflets, are in nodules from Mazon Creek. The others, small ones, as Plate VII, f. 4, are from Montevallo coal mines, communicated by Mr. T. H. Aldrich.
NEUROPTERIS COLLINSII, Lesqx.Pinnules large, ovate or obovate, broadly obtuse, entire; base truncate, large; veins inflated at the base and there distant, dichotomous, slightly arched, becoming thin, close, and more divided from the middle upwards.
Geol. Rept. of Ill., IV, p. 382, Pl. V, Figs. 5, 6.
Schp., Paleont. Veget III, p.473.
The venation and the large size of the pinnules are the same in this species as in the former. The leaves are comparatively longer, averaging six centimeters long and three broad, oblong or obovate, gradually narrowing to the base, not rounded and cordate; the veins more distinct, though quite as thin, and the surface flat not inflated. In the former species the leaflets are marked in the middle by a depression like an effaced costa, which is not apparent upon those of this species. The differences are, perhaps, not marked enough to authorize a separation.
Habitat—Same as the former; nodules of Mazon Creek.