LEPIDODENDRON". 157 



length of the cushion from the apex, rhomboidal, upper and lower 

 angles rounded, prints indistinct. Field flat, "without keel or 

 glands, and apparently without well - marked transverse ridges. 

 Leaves short, acicular, persistent, uninerved. 



Carruthers, in his original description of these fossils, says 

 "fruit a cone?," but he merely deduces this conclusion from the 

 occurrence of numerous detached megaspores which he regards as 

 belonging either to SigiUaria, or to Flemingites, in close association 

 with the stems. It was on the characters of the supposed cone that 

 he referred these specimens to the genus Flemingites rather than 

 to Lepidodendron. 



There is no specimen of a cone among these South American 

 fossils. The stems themselves, as Zeiller l has already shown, 

 undoubtedly belong to a Lepidodendron, and are closely similar to 

 European species of that genus. It is quite possible that the 

 megaspores (see p. 175) associated with them may eventually 

 prove to belong to L. Pedroanum, as Carruthers believed, but at 

 present there is no positive evidence on this point. 



Carruthers states that the leaves of L. Pedroanum have a parallel 

 nervation, and figures them as such. Zeiller 2 has, however, made 

 a more detailed study of these organs, and finds that the surface 

 is striated longitudinally by fine and close, parallel striae. In 

 addition, there appear at first sight to be three parallel nerves, 

 of which the two lateral are often better marked than the median. 

 He shows that the central nerve is the single vascular bundle of 

 the leaf, and that the two lateral ridges correspond to two stomati- 

 ferous furrows, such as are found to occur running longitudinally 

 through the leaf of a SigiUaria. 



Zeiller 2 has already pointed out that the fossils from Argentina, 

 identified by Szajnocha 3 as L. Pedroanum, are not identical with 

 Carruthers' species. 



Bodenbender 4 has recorded from Argentina another Lepidodendron, 

 L. Sternhergii, Brong., which is a typical and common species in 



1 Zeiller (95 2 ), p. 6Q7 ; (95 1 ), p. 962. 



2 Zeiller (95 2 ), p. 60S. 



;; Szajaocha (91), p. 207, pi. ii, figs. 2, 3. 

 1 Bodenbeuder (96), table opposite p. 770. 



