| 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 |
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All Four Volumes: Scans and Webpage ©George Langford III, 2011 |
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In this group I place the genera Megalopteris, Daws., related to Neuropteris by the nervation and to Alethopteris by the position of the leaflets, decurring on the rachis; Taeniopteris, Brgt., which is diversely considered by the authors in regard to place and affinity; Neriopteris, Newb'y; Danaeites, Goepp.; Orthogoniopteris, Andrews, and Protoblechnum, Lesqx., whose relation to the two first of the above genera is considered in the descriptions. I place in this group also a remarkable leaf, Idiophyllum, related by its general character to Phlebopteris (Dictyophyllum) Nilsoni, Brgt., and by its peculiar nervation to Dictyopteris. |
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Fronds very large, simply pinnate; ultimate pinnae (or pinnules) oblique, sublinear or lanceolate, entire, the lower side broadly decurrent on the rachis, which thus becomes alate, the upper narrowed in a curve, confluent; midrib thick; canuliculate on the upper surface, half cylindrical on the lower, gradually narrowed but distinct to the apex of the leaves; veins open, cmerging from the rachis in a more open angle of divergence, curving upwards in reaching the borders, close, dichotomous. Except for the characters of the venation, this genus is not separable from Danaeopsis, Heer. The veins are more oblique, much thinner, dichotomous, generally forking once near the base, and one of the branches or both forking again near the border. |
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Frond very large; rachis half round; pinnules linear or oblong, abruptly rounded to a short acumen; costa very thick, continuous, veins open, curved down in joining the rachis and inclined upwards towards the borders, dichotomous, thin, close, distinct. This species is indeed a magnificent one, by the size of the pinnae of which a small fragment only could be figured. The sketch of part of one of the largest, made in place by Mr. Southwell, who discovered the remains, is eleven and a half centimeters broad, about in the middle, with a half round costa, twelve millimeters thick. Another sketch of the terminal portion of a pinna shows the upper leaflets seventeen centimeters long from the base of the midrib to the apex and only three centimeters broad. According to this, and by comparison, the largest leaflets should have measured. fifty to sixty centimeters in length. It is not surprising that notwithstanding active researches this plant could be obtained only in fragments. The upper pinnae are disposed about like those of Plate XXIV, f. 2, the main rachis becoming gradually narrower, passing up to the apex of a terminal pinnule of same form and size as the lateral ones. The lateral veins are gradually in a more open angle of divergence to the rachis, in descending towards the base of the leaflets, and thus are nearly in right angle upon the decurrent base which tapers downwards to the point of connection with the upper border of the inferior pinnule, joining it quite near the rachis. Habitat—Lower beds of the Coal Measures, sub-conglomerate, near Port Byron, Ill., Mr. J. H. Southwell. |
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Ultimate pinnae alternate, oblique, linear-lanceolate, obtuse, broadly decurrent; medial nerve flat, dissolved below the apex; veins numerous and fine, in an acute angle of divergence, dichotomous, curved in passing to the borders. From the former species this one evidently differs by the obtuse leaflets, the flat midrib and the lateral veins in a more acute angle of divergence. The average size of the pinnules is one and a half centimeters wide and ten centimeters long; the terminal leaflet is shorter and narrower. The author describes the margin of this species as some times distantly and irregularly crenate. This is probably a casual appearance caused by laceration or maceration of the borders as in all the species known until now the margins are positively entire. Habitat—Base of the coal measures near Rushville, Ohio. Discovered by the author, with all the other specimens described from that locality. |
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Pinnules smaller, lanceolate, obtusely acuminate; veins more open and less numerous. Except that the size of the fronds and pinnae is smaller, the species has about the same characters as the former ; the veins are only more open, more distant and distinct. Habitat—Same as the former. |
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Pinnules short, ovate, or broadly lanceolate, obtuse; venation same as in thc former species. The pinnules are broader and comparatively shorter. It is the essential difference which separates this form from Megalopteris minima. The author remarks that in the decurrent laminae, the veins become more open and nearly in right angle to the rachis. This character is observable upon all the species of this genus. It results from the deviation of the decurring borders from the normal line. In unequilateral pinnae, as in those of Megalopteris abbreviata, the angle of divergence is different upon each side of the pinnules. Habitat—Same as the former species. |
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Pinnules comparatively small, lanceolate, equally narrowed to the acuminate point and to the decurring base; midrib narrow, continuous; lateral veins on an acute angle of divergence, distinctly curved upwards in reaching the borders, more distant and thicker than inMegalopteris Southwellii. This fine fragment appears to represent a young frond preserved in its integrity. The lower pinnules are like fasciculate, or two, or three-lobed by forking of the medial nerve at their base, a division very similar to that of Neuropteris fasciculata, f. 6, of Plate XXIV. These lower pinnules are not decurrent, but the rachis becomes winged, and its borders veined lengthwise by parallel fascicles of vessels derived from the central axis, as in the basilar stalks of some fronds. This species differs already from Megalopteris Southwellii by the venation; for according to the remarks of the discoverer, the veins in this last species become more distant proportionally to the size of the leaves, hence the greater distance of the veins on small pinnules, like those of this Fern, should already authorize a specific separation. But there is also a marked difference in the size of the pinnules and in their form; for in this species, the leaflets are truly lanceolate, gradually narrowed to a sharp and long acumen, while in Megalopteris Southwellii, the pinnules are linear, narrowed in rounding to a very short point. Habitat—Lower beds of the coal measures of Ills., Mr. I. H. Southwell. |
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Pinnae ovate, rapidly narrowed and rounded to the apex, broadly decurrent; midrib narrow; veins thin, close, dichotomous and distinct. Comparing also this species with Megalopteris Southwellii, it differs by the size and shape of the pinnules, which, much shorter, are ovate, narrowed to a short acumen. The midrib is narrower; the venation is of the same character. Habitat—With the former. |
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Pinnules large, sometimes bifurcate above the middle by the splitting of the medial nerve, veins less curved than in the former species. The author, comparing this form to Megalopteris Dawsoni, Hart, Acad. Geol., 2d, Ed., p. 550, remarks that it differs by the surface not rugose, the veins less divided and less curved. In the number of species described above we have, it seems, two peculiar types, especially differing by the size of the midrib. It may be, however, that the specimens obtained from Illinois represent the under surface of the leaflets, with a half round large costa, while those obtained in Ohio show the upper surface with the medial nerve flattened. Of Megalopteris Dawsoni, Hart, the author, says that the midrib is thick, and shows a strong tendency to split up obliquely to the rachis. From the figures, however, the midrib is very thin, indeed not marked at all. The general characters of the species described either by Prof. Andrews, from Ohio specimens, or by myself, from fragments received from Mr. Southwell, appear remarkably similar in each peculiar group. Adding this to the uncertainty about the exact conformation of the midrib, it would not be amiss to suppose that we have here only two species, represented each by the specimens of the two localities, the fragments under divers forms and size, being referable to the various parts of the plants; some to old fully unfolded fronds; others to young and basilar ones. Though it may be, in regard to the specification of the fragments, it is certain that they pertain to a group of ferns which, at the beginning of the carboniferous epoch, represents this family by plants as remarkable by their magnitude as by the elegance and the beauty of their forms. No types in the successive developments of the vegetation of the Ferns of the coal seem comparable to that of the Lesleya and the Megalopteris. |
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Pinnules fasciculate at the top of the fronds, lanceolate, acuminate, gradually narrowed downward; borders reflexed; medial nerve narrow, but thick and distinct, precurrent; veins oblique, distant, forking twice, moderately curved in passing to the borders. The only specimen received of this species is figured. It represents the upper part of a pinna or of a frond with four pinnules, whose base is destroyed. They occupy the same position as those of f. 2, of Plate XXIV, and from their direction towards a common axis, they appear to be joined to the rachis, like the divisions of the fronds of Megalopteris; for the shape of these leaflets and the venation are also of analogous character. The pinnules, larger above the middle, are narrowed to a short, slightly truncate acumen, formed by the prolongation of a thick costa beyond the borders, which, reflexed as they are, do not entirely cover its top. The duplication of the borders is much like the marginal folding, covering the fructifications of some Ferns of our time—Pteris, Pellaea, etc. It is, however, more regular, and though the doubled borders can be separated in fragments, they do not seem to cover any fruiting organs; at least, close and repeated examinations have failed to show under them any trace of sporanges, but merely fragments of a very thin pellucid, narrow membrane. The marginal mode of fructification, if positively ascertained, these Ferns to Alethopteris, a genus to which Megalopteris is related also by the decurring base of the pinnules, forming prolonged wings along the rachis. The substance of the leaves of this species is comparatively thick; the veins distant, more oblique still than in Megalopteris fasciculata; the pinnules are also shorter and broader. However, the facies of the remains representing these two forms is so much alike, that, if any trace of fructifications has been observed, I should have considered the fragments as referable to the same species, for there is often an appreciable difference in the characters, venation, sub-divisions of the pinnules, etc., between the sterile and fertile fronds of the same kind of Ferns. Habitat---Lower carboniferous near Port Byron, Ill. Mr. Southwell. |
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Fronds simple, large, linear; medial nerve (rachis) canaliculate, strong; veins open, or in right angle, thin, forking a little above the base or more generally simple, parallel, sometimes joined to a marginal nerve; fructifications unknown. The species formerly admitted in this genus by authors are distributed now, Schp. Paleont. veget., I, p. 600, in the Genera Taeniopteris, for species in the Permian and Permo-Carboniferous; Angiopteridium, Schp., for those of the Jurassic, mostly of East India; Marattiopsis, Schp., for one only, tertiary; Oleandridium, Schp., for triasic and tertiary species. Macrotaeniopteris, for those in the Lias and Oolithe, some of them also Australian and East Indian; and Danaeopsis, Heer, for two Triassic plants. From this it appears that no species of Taeniopteris has been found until now in the true carboniderous measures, or below the New-red (Permo-Carboniferous.) |
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Fronds simple, large, linear; midrib broad, canaliculate in the middle, flat on the borders; veins in right angle, very thin and close, distinct, parallel, mostly simple. A fine and remarkable species known only by the fragment figured. The width of the leaf, nearly five centimeters broad, indicates its length at fifteen centimeters. The fragment is nearly linear, a little more enlarged toward the lower part; the borders are perfectly entire, slightly inflated as by a marginal nerve, lacerated only by maceration and erosion; the substance is thin. The veins are in right angle to the broad midrib or rachis, mostly simple, rarely forking once near the base, three to four per millimeter; contiguous, scarcely varying in their horizontal direction from the point of attachment to the border. Taeniopteris multinervis , Weiss., (Taeniopteris carbonaria, Schp.), has some affinity to this Fern. The veins of the European species are more distant, distinctly curved down to the rachis, more divided, and the costa or rachis not channeled. Habitat—Sub-conglomerate measures of Alabama. Locality not indicated. The specimens sent for determination by Prof. Eug. A. Smith were without labels. But except a few fragments of Lepidodendron from the Anthracite of Wilkesbarre, all the others were positively from the Alabama coal fields. The stone whereupon this leaf is preserved is of the same nature and compound as that of a number of other specimens from Helena coal mines. |
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Frond pinnate or bi-pinnate; rachis strong, punctate; pinnules lanceolate, simple, entire; medial nerve strong, extending from base to summit; secondary veins given off at an acute angle, numerous, simple or forked at the base, parallel, equal; fructifications marginal. |
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Frond pinnate or bi-pinnate; pinnutes diverging from the rachis at an acute angle, lanceolate, acute, rounded to the point of attachment, sessile or short petioled; midrib strong, straight, percurrent; veins coming out from the rachis at an acute angle of divergence, slightly curved at the base, crowded, simple or forked near the base, parallel and equal. The author says of this species, that it is, by some of its characters, similar to Phyllopteris antiqua, Daws. Acad. Geol., 2d Ed., p. 484, f. 166 E, differing by the nervation which in the Ohio species has an equal degree of affinity to Alethopteris and Taeniopteris. Comparing the upper part of the pinnules, as figured by the author, to the fragment of Atlas, Plate XXIV, f. 4, the similarity of shape is striking; the flexure of the borders is the same, the leaflets are only more distinctly acuminate in this last figure. The affinity is eliminated by the great difference in the venation which in our plant is of the Megalopteris type, while from the figure of Dr. Newberry, the veins are straight, simple, though slightly oblique and parallel. The author remarks that the enlarging, f. 3, does not correctly represent the venation, the veins being forked at the base and somewhat curved at their point of junction to the rachis. Even with this correction, the venation of both species seems of a different character; for indeed, that of Megalopteris fasciculata is positively of the same type as in the other described forms of the genus, while Dr. Newberry compares the venation of his species to that of Taeniopteris. As the base and mode of attachment of the leaflets of Megalopteris fasciculata is not known, a definite comparison of these two plants cannot be made. Habitat--Base of the coal measures. Coal No. 1, of Summit Co., Ohio. Discovered by the author. |
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Frond simply pinnate; pinnules alternate, lanceolate or oblong-linear, rounded and tapering to an acute point, enlarged and decurrent on the lower side to an auricle rounded in the upper part in joining the lamina a little above its point of attachment to the rachis; medial nerve thick, ascending to the apex; nervules fine and numerous, uniform, at right angle to the midrib, decurring to it at the point of attachment, forking once near the base. From the remarks of the author, this genus is allied to Taeniopteris, Brat., Angiopteridum, Schp., and Neriopteris, Newb' y, having more the character of Danaea than any of the Pecopterids of the coal measures. It is however allied to Alethopteris by the decurrent base of the leaflets. |
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Specific characters same as those of the genus. This fine Fern is represented by two fragments of a same pinna thirty-seven centimeters long, linear obtuse in outline. The pinnules diverging from the rachis at an angle of 25°, are nine to eleven centimeters long, two centimeters wide, parallel, close, imbricated on the borders, linear to near the top where they taper in a curve to a more or less definite point; borders undulate or slightly revolute; nervation of the genus. Habitat—Base of the Coal measures in Perry county, near Rushville, Ohio. |
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Character of genus. Differs from the preceding by a relatively stronger rachis, the pinnae of a thicker substance, shorter, lanceolate, more distant; the medial nerve not as thick and the veins fine, closer, less curved toward the margin which is somewhat thickened. The pinnules are about six centimeters long, fifteen millimeters broad. Habitat—Same as the former. |
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Fronds pinnate; secondary veins coming out in right angle from the primary straight nerve, simple or dichotomous; sporanges on the lower side of the lamina, placed in rows from the medial nerve to near the borders along the lateral veins, oval or linear, exannulate. From the definition of the genus as admitted by Schimper, the fronds of the Danaeites are merely pinnate, as they are also in all the living species of Danaea. Goeppert however, Syst., p. 380, Pl. XIX, f. 4, 5, describes as Danaeites asplenioides, a species whose frond is at least bi-pinnate and whose sub-divisions are evidently Pecopterid. This species, by its fructifications, does not appear related to Danaea, the sporanges being merely oval, placed near the midrib, and not distinctly in continuous rows as they are in living Ferns of the genus. Danaeites Schlotheimii, Deb. and Ett., Acrob. d. Keide., p. 22, Pl. III, f. 1, a Cretaceous plant, has a marked relation to species of Danaea by its simply pinnate fronds, its fructification and the venation, and Danaeites firmus, Heer., Fl. Arct., I, p. 81, Pl. XLIV, f. 20-22, also Cretaceous, has its fronds pinnate or bi-pinnate and its fructifications marked by a group of oval sporanges in juxtaposition to the midrib. In two of the Danaeites, therefore, there is a difference in the characters of the sporanges and also in the divisions of the fronds from the general type as known from living Ferns. Considering that the species described here, has by its fructification a remarkable concordance of character with those of the species of Danaea of our time, its placement into this genus seems legitimate, though the frond is at least tripinnate, not simple. By this character and by the venation this plant is related to Callipteridium or to Alethopteris. |
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Frond very large, tripinnate; primary pinnae lanceolate; secondary divisions linear-lanceolate, variable in length becoming gradually shorter toward the apex; pinnules oblong, very obtuse, connate near the base, the upper ones to the middle, in joining the terminal ovate obtuse leaflet; midrib thick, abruptly effaced near the apex; veins slightly oblique, simple or forking once, strong and close; fructifications in linear series of sporanges passing in an upward curve from the midrib to the entire borders. The substance of this Fern is coriaceous; the surface is a thick epidermis, covering and partly obliterating the venation which is distinctly seen only where this epidermis is erased. The . general facies of the plant is that of an Alethopteris. Indeed by the division and forms of the leaflets, it has the greatest affinity to Alethopteris Serlii and to Callipteridium Sallivantii. Plate XXVIII, f. 2 is part of a large specimen, thirty centimeters long, with broad rachis, one centimeter at the base, bearing alternate, sub-linear pinnae, the lower ones fertile, longest in the middle, eight centimeters, gradually shorter downwards, the upper ones sterile also gradually shorter, becoming simple pinnules towards the apex as in all the species of Alethopterids. The specimen is a counterpart of the lower side of the pinnae, deeply impressed into the stone, the fructifications being partly left attached to the matter in continuous, linear, somewhat broad rows of sporanges, covered by the thick epidermis, which, when removed, leaves the stone marked as Plate XXVIII, f. 2a. The intervals between the pointed lines separate the series of agglomerated sporanges, distinct on the borders of the linear zones by points or small indentations, as seen on the pinnules of the left side of Plate XXVIII, f. 2a. The form of the pinnules is the same in the fertile as in the sterile pinnae; they are oblong, very entire, obtuse, variable in length and width, according to their position, the largest one in Plate XXVIII, f. 1, being two centimeters near the base of the pinnae, gradually shorter to eight millimeters under the terminal leaflets. The veins are thick, parallel and very close, as joined to each other along the borders, simple or forking near the base; no trace of veins is discernible upon the fertile leaflets. Habitat—Shale above the Coal of St. Clairsville, equivalent of the Pittsburgh bed. Communicated in numerous specimens by Mr. P. W. Emerson of that place. |
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DANAEITES MACROPHYLLUS, (Newb'y,) Lesqx., Plate XXV, Figs. 4-6.
Frond pinnate; pinnae or
pinnules sublinear, narrowed into a deltoid slightly obtuse apex;
borders undulate or irregularly scalloped; base obliquely deeply
cordate; medial nerve straight; lateral veins in right angle to the
costa, scarcely curved downward in reaching it, crowded and numerous,
very fine, simple or forking once.Alethopteris macrophylla, Newb'y, Geol. Rept. of Ohio, Paleont., I, p. 383, Pl. XLVIII, f. 3, 3a. This definition is that of Dr. Newberry, with scarcely any modifications, and agrees so well with the characters of the fragments represented in our plate that it is not possible to doubt identity; the only difference being that the Ohio leaves are slightly reflexed on the borders, while they are flat in ours. The veins are so fine, so exactly in right angle to the midrib, and so little divided, that at first sight the plant seems referable to Taeniopteris. But in this genus, the fronds or pinnae are simple, while the shape of the base of the pinnules indicates those of this species as evidently pinnate. Its relation to the Alethopterids is contradicted by the unequal, deeply cordate base of the leaflets; a character which is not seen in any of the pinnules of this group; and also by the large size of the leaves and their nervation, the fragments indicating ultimate pinnae ten to twelve centimeters long, and two to two and a half centimeters broad. Their lamina is irregularly scalloped or cut on the borders, as the leaves of some species of Taeniopteris. By the large size of the leaflets, and by their venation, this fossil Fern is related to Danaea. Some species of this genus bear simple pinnae, prolonged at the base into an obtuse auricle, as in the fragment, Atlas, Plate XXV, f. 4. Habitat---Youngstown low coal, No. 1 of the Ohio Geol. Rept.; same horizon as Talmadge, the locality where Dr. Newberry obtained his specimens. |
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Leaves small, round, or broadly obovate; medial nerve thick, gradually narrowed and effacing in joining the borders; lateral secondary veins sub-opposite, thick, passing in an inside curve towards the borders, gradually effaced in the reticulation; venules more or less continuous; sometimes crossing each other in contrary directions, and forming, by intersections, regularly quadrate or rhomboidal meshes. The leaf, the only one for which the genus is established, is, by its peculiar areolation, related to Dictyophyllum, Ll. & Hutt., and might be described under this name, but for the pinnate character of the leaves of all the specie referred to this last division. The English authors remark that the name Dictyophyllum, may be advantageously employed for the description of fragments of doubtful character referred to Ferns, leaving that of Phyllites for those positively dicotyledonous; and that other names may be invented for plants showing remarkable peculiarities in the arrangement of the veins, etc. The only fragment figured to which this leaf may be compared, is that in St., Fl. d. Vorw., 1, Pl. XLII, f. 3, which, with f. 2, named Phillites, pertain to the lower Lias of Hoer, Scandinavia. F. 2 is referred by Schimper to Dictyophyllum Nillsoni, and is evidently part of a pinnate-lobate leaf; f. 3 is not mentioned or described anywhere. It shows only one side, the half of an oval entire leaf, with secondary veins oblique, parallel, and close. The strong nervules, about as distant as the veins, are in right angle and simple, passing parallel through the areas between the veins, forming a large quadrate areolation. I think that it would be advisable to refer Sternberg's plant to the same generic division; for the nervation is like that of our leaf, and if the mostly destroyed side had the same character as the preserved part, the whole would represent an oval, entire leaf, and the generic relation would then be confirmed. |
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Pinnule nearly round, more enlarged at the very obtuse nearly truncate apex; borders entire, nervation as described for the genus. The leaf, attached to a rachis by its rounded base, or by the thickened base of the costa, is four centimeters long, four and a half centimeters broad in the upper part, where it is somewhat shrunk by compression of the upper border into the stone. The characters of the secondary veins indicate it as entire all around, the primary nerve becoming gradually thinner to near the border, where it is effaced, and the lateral, parallel, secondary veins (four pairs) curved upwards, being also gradually narrowed, and effacing close to the border in the same manner as the midrib. The tertiary divisions are real nervilles, though, by their direction, they appear as branches of the lower secondary veins. They are parallel, thick, generally continuous, passing over the secondary nerves, or sometimes curving back, and re-crossing the areas in a contrary direction, thus composing regular quadrangular, or broadly rhomboidal meshes, as seen on the left side of the figure. The peculiar character of the venation seems, therefore, more intimately related to that of the fragments f. 3, Pl. XLII, of St., l.c., than to any of the species of Phlebopteris or Dictyophyllum described by the authors. At first sight the likeness of this fossil fragment to some dicotyledonous leaves is striking. None of the Ferns of our time have any relation to it. The large meshes, either simple or double by the crossing of the nervilles, do not show any trace of intermediate areolation like that observed in Clathropteris. Habitat—Mazon Creek in nodules, lowest strata of the middle coal measures, close upon the Millstone Grit; communicated by Mr. S. S. Strong. The preservation of this leaf, that of species of Spirangium, and of a number of other vegetable remains never seen anywhere else in the Coal measures of this continent or of Europe, seem to prove that a large number of the plants of the Coal measures, those of a thin substance, easily destroyed by maceration, have, as yet, escaped research, and that a limited portion only of the remarkably rich flora of the coal is known to botanists. |
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