LYCOPODIALES— LEPIDODENDRE.E— LEriDODENDRON. 187 



the axis. Owing- to the unfortunate lack of material so preserved as to show 

 the internal structure of the stems, we are left to search for fruiting cones 

 in wliich the arrangement of the sporangia Avill be discernible. I anticipate 

 that the cones will be found to show the characters of SiilienophyUum, and 

 I have very little hesitation in unequivocally referring it to that genus. 

 Should additional material substantiate such a reference it is probable that the 

 type of fig. 2 of pi. iii of Coal Flora will be placed in or near Asterophyllites 

 gracilis Lx., or A. grandis Stb., with which in many respects it agrees. 



I am not sure whether or not a specimen of Asterophyllites fascicidatus 

 was the basis of the identification by Lesquereux of Splienophyllum furcatiim 

 Lx. in the Missouri flora, but I am inclined to believe tliat the enrollment 

 of tlie latter species in the list from Henry County was based by him on 

 fragments of S. emarginatum Brongn., in which the leaves are sometimes 

 dissected nearly to the base. The true 8. bi/urcafum, as described from the 

 "coal-bearing shales" of Washington County, Arkansas, is quite different 

 from anything I have yet seen from the Missouri Coal Measures, and appar- 

 ently constitutes a good species of some stratigraphic value. 



Localities.— Owen's coal bank, U. S. Nat. Mus., 5539, 5542, 5622, 5637, 

 5639, 5675; Deepwater, U. S. Nat. Mus., 5540, 5658; Gilkerson's Ford, 

 U. S. Nat. Mus., 5641 ; Hobbs's coal bank, U. S. Nat. Mus., 5543. 



LYCOPODIALES. 



LEPIDODENDREZE. 



LEPIDODENDROIf Sternberg-, 1820. 



1820. Lepidodendron Sternberg, Fl. d. Vorw., vol. i, fasc. 1, p. 25; tent. (182.5), p. x. 

 1822. Sagenaria Brongniart, M6m. mus. hist, nat., vol. viii, p. 239. 



Of the five species of this genus occurring in the Lower Coal Measures 

 in the region of Henry County, Missouri, two, Lepidodendron Brittsii Lx. 

 and L. lanceolaUim Lx., belong to older types of the genus, the former hav- 

 ing been probably derived from L. Volkniannianum of the culm or some 

 related species, while the latter is most intimately coimected with the L. 

 Sternhergii as identified by Pi'ofessor Lesquereux from the Pottsville series. 



The study of the internal structure of a large number of the species of 

 this genus shows a very great diversity of organization, especially with ref- 

 erence to secondary or exogenous growth, some of the stems or branches 

 presenting only the primary growth, while others contain a very elaborate 



