LYCOPODIALES— LEPIDODENDRE.E— LEPIDODENDEON. 191 



Usually when the base of the leaf is not inclmed somewhat downward 

 in the fossil state, the base of the midrib is expressed as a lo\v, rounded 

 ridge vanishing quickly in passing a short distance downward from the 

 base of the leaf scar. This feature, which is indicated in fig. Ih, loc. cit., is 

 well shown in our Fig. 2, PL LII, or Fig. la, PL LIV. The respiratory 

 appendages generally lie rather close to the Avascular scar and have been 

 drawn conventionally in the Coal Flora as the lateral mammillee of the leaf 

 scar. In none of the specimens, including those studied by Professor 

 Lesquereux, have I been able to discover these lateral traces within the 

 leaf scar. This is probably on account of the very close proximity of the 

 broken carbonized upper and lower boundaries of the leaf cicatrix. 



The "ligular scar" is not generally apparent in the aA^erage specimens, 

 but may frequently be found by a careful search of the bolsters on which the 

 epidermis is well preserved. In No. 5489 of the Lacoe collection,^ in which 

 the bolsters were drawn downward in the process of fossilization, the leaf 

 scars being consequently somewhat straightened, we find it clearly preserved 

 a little over .5 mm. above the leaf scar as a minute mammilla in a slight depres- 

 sion. Any other appendicular markings or generic characters are either 

 wanting or they are obscured by the transverse wrinkles in the upper field. 



An example of the smaller and more slender leafy twigs is shown in 

 PL LII, Fig. 1, while a fragment of a more robust branchlet is illustrated 

 in PL LIV, Fig. 1. Branches of this size strongly resemble in their gen- 

 eral aspect the corresponding portions of Lepidodendron Haidingeri Ett. 

 or L. lanceolatwn Lx. The leaves are thin, concave beneath at the base, 

 near which they are usually bent backward more or less before curving 

 outward or upward. Frequently in the larger branches, like that photo- 

 graphed in PL LIII, Fig. 1, the slender tapering tips are hardly so high as 

 the bases. Occasionally they are found adhering to stems of considerable 

 size, such as that shown in fig. 2, pi. Ixiii, of the Coal Flora. 



It would be very interesting to know the strobili of this species. It 

 is possible that Lepidophyllum or Lepidostrobus Jenneyi, which is not rare in 

 these beds, may belong to the branches in hand. The facts that each is the 

 most abundant representative of its respective genus here, and that neither 

 has, so far as I know definitely, been found elsewhere, warrant a suspicion 

 that they may be portions of the same tree. 



'Identified and labeled by Professor Lesquereux, from "Clinton, Missouri." 



