344 



A CONTRIBUTION TO THE KNOWLEDGE OF 



top of the vascular scar, measures one and a half inches; from the top of the vascular scar 

 to the upper end, fourtcen-sixtcenths of an inch. Through the kindness of Prof. Lcs- 

 qucreux, I have had access to the second volume of Sternberg's Flora der Vorwelt, and find 

 that this plant is much more closely related to L. aculeatum than L. caudatum, Ung., to 

 which I formerly supposed it related, having only Unger's short description to guide me. 

 The principal difference between L. aculeatum and it, is to be found in the position of the 

 vascular scar. From the bottom of the leaf-scar to the top of the vascular scar, is in L. 

 aculeatum one inch and a half, and from the top of the vascular to the top of the leaf-scar 

 eight-sixteenths of an inch, so that the relation of the two is as three to one, whilst in L. 

 urarum it is as twelve to seven. Broad Top Coal Region. 



L. DREPANAsriS, Wood. Leaf- scars large, rhomboidal with rounded angles and some- 

 what curved margins ; margins narrow, very slightly elevated ; vascular scars triangular or 

 sub-rhomboidal, their transverse diameter much the greater, elevated above the general sur- 

 face, furnished with three dots and situated near the apex of the leaf-scar ; below them is 

 a crescentic, shining slope, on which are placed the roundish tubercles ; appendages parallel 

 to the margin; median line nearly obsolete, but crossed by numerous short, transverse 



L. drepanaspis, Wood. Proc. A. N. S., vol. xii, 1860, p. 240. 



Lepidodendron icthyolepis, Wood. Cortex thin, leaf-scars subtriangular, kite-shaped ; 

 vascular scar strongly elevated, rhomboidal, oval, with the ends acuminate, without in- 

 ternal markings, situated in the apex of the leaf-scar ; appendages well marked, elevated ; 

 median line elevated, pronounced, smooth ; tubercles wanting. 



The elevation of the upper portion of the leaf-scar gives an appearance of imbrication, 

 which suggested the name. 



Lepidopldoyos icthyolepis, Wood. Proc. A. N. S., vol. xii, 1860, p. 240. 



I;. DumuM, Wood. Cicatrices lanceolate, acuminate at the base and apex, strongly 

 convex, cristate along the central line; margin very narrow, flexuous ; vascular scar linear 

 lanceolate, slightly enlarged in the middle, elevated. 



L. dubium, Wood. Proc. Acad. Nat. Sciences, New Series, vol. xii (1860), p. 238. 



This species is allied to L. rimoswm and L. undulatum of Sternberg. It differs from 



