NATURAL SCIENCES OF PHILADELPHIA. 239 



with apex and base acuminate ; margin sunken, flexuous, very narrow ; vascu- 

 lar scars lanceolate. 



In our specimen the vascular scars are almost obsolete and have a slight 

 bulbous enlargement in the centre. Where the bark remains, the crest of the 

 scar alone reaches the surface. We place this plant, with some hesitation, among 

 the Lepidodendra. It is, however, allied to L. rimosum and L. undu la- 

 tum, and with them ought perhaps to be erected into a separate genus. If 

 this should hi found advisable, we would propose the name Acrostigma. Lo- 

 cality and position uaknown. Collection of the Academy. 



L. in gens n. sp. Cicatrices sub-rhomboidal, with apex and base acumi- 

 nate, and base curved ; margin distinct, furrowed, regularly flexuous ; vascu- 

 lar scar sub-triangular, rounded at its apex, with the angles acute ; tubercles 

 distinct obovate ; middle line almost obsolete, its situation marked by a shal- 

 low groove. 



This large species, somewhat resembles L. giganteum Lesq. from which, 

 however, the outline and disposition of leaf-scars separate it. 



L. m e k i s t o n, n. sp. Cicatrices, elongate with both apex and base acumi- 

 nate and the base curved ; margin raised, regularly flexuous ; vascular scars 

 sub-rhomboidal, with acute angles and marked with two or three dots ; ap- 

 pendices distinct, very long, tubercles obovate ; medial line deeply furrowed, 

 transversely rugose. 



The internal markings, of cicatriculi as well as the tubercles, are very often 

 badly preserved. The general form of main scar resembles L. Lindleyanum 

 Ung., whilst the raised border and form of vascular scars ally the plant to 

 L. aculeatum Sternb. The more elongated cicatrix and the acute angles 

 of the cicatriculi, separate it from the latter species. It also differs in the 

 situation of tubercles and length of appendices. Locality and position un- 

 known. Cabinet of the Academy. 



L. w e n i, n. sp. Cicatrices rhomboidal with somewhat curved base and 

 apex ; margin distinct, flexuous ; vascular scars rhomboidal, placed near the 

 apex of the cicatrix ; appendices parallel to the margin ; medial line well 

 marked, flexuous. 



Syn. L. aculeatum Sternb. n. sp. Owen Geological Survey of Wisconsin, 

 Iowa, &c, vol. ii. pi. vi. figs. 1, 3. That the impressions there figured are not 

 L. aculeatum Sternb. we think is shown by the following considerations : 

 1st. The shape and relative position of the leaf-scars in the two are quite dif- 

 ferent. 2d. The vascular scars differ in outline and in Sternb. 's species they 

 are marked with three dots which are wanting in Owen's. 3d. Tubercles are 

 present in L. a c u 1 e a t u ra Sternb. but not in Owen's figures. Finally the 

 margins of the cicatrices differ. 



The outline of our specimens differ somewhat from those figured in the Re- 

 port, but we think that the species are identical. Locality, unknown. Posi- 

 tion, Sandstone below the coal? Cabinet of the Academy. 



L. dikrocheilus, n. sp. Cicatrices sub-elliptical with apex and base 

 acuminate and the base curved ; margin raised, broad, regularly flexuous, vas- 

 cular scars sub-rhomboidal, with apex and base rounded and angles at the 

 sides very acute, marked with three dots ; medial line almost obsolete, slightly 

 rugose. 



The margin of this species so bifurcates, that on the right side it receives an 

 offset from the same side of the neighboring scar ; thus making it nearly twice 

 as wide on the right hand side below, and on the left, above. Locality, Broad 

 Top Coal Region. Position, Roof of Cook's (upper) Seam. Private collec- 

 tion. 



L venustum, n. sp. Cicatrices rhomboidal, with their base truncate ; 

 margin narrow, flexuous ; vascular scar rhomboidal, placed above the middle 



I860.] 



