FEENS— MEGALOPTEEIDE.^— LINOPTERIS. 139 



Dawson' as Dolerophyllum pennsylvanicum. Tliese, too, are Cyclopteroid, 

 though smaller, thicker, and more fibrous than any of the other Cyclop- 

 terids. These fertile or polleniferous disks are now known from several 

 localities in this country, and the fact that Cyclopteroid specimens of the 

 same nature as N. dilatata are present in the same beds justifies the antici- 

 pation that should specimens showing the organization of the leaf be found, 

 these would prove generically identical with the similar forms froni the 

 Old World. 



Localities. — Hobbs's coal bank, U. S. Nat. Mus., 5471; Pitcher's coal 

 bank, U. S. Nat. Mus., 5470, 5658, 5672. 



LINOPTERIS Presl, 183S. 



1835. Dictyopteris Gutbier (non Larnour.), Abdriicke, p. C2. 



1838. HHopteris Presl, in Sternberg: Versuch, vol. ii, facs. 7-S, p. 167. 



1897. Linopteris Presl, Potonie, Lebrb. d. Pflanzenpal., p. 153. 



LiNOPTEBIS GILKBESONBNSIS 11. Sp. 



PI. XLI, Figs. 7, S; PI. LXI, Fig. 1/. 



1897. Dictyopteris sp., D. White, Bull. Geol. Soc. Amer., vol. viii, pp. 297, 300. 

 1899. Dictyopteris gilkersonensis D. White, 19th Ann. Eept. U. S. Geol. Surv., pt. 3, 

 p. 510. 



Pinnules open, rather distant, alternate, sessile by a narrow attachment 

 to a slender striate rachis, 5 mm. to 2 cm. or more in length, 4 to 7 mm. 

 in width, oblong-ovate, tapering from near the base toward the round sum- 

 mit, nearly straight, hardly subfalcate, the base nearly equilateral, of rather 

 thick texture and sparsely punctate; midrib of moderate strength, irregular 

 above the middle ; nerves very coarse, but few primary nerves, very oblique, 

 anastomosing near the bifurcations, touching the margin obliquely; areoles 

 comparatively few, very broad in proportion to the length, trapezoidal, 

 roundish at the distal end, very long and oblique near the midi-ib, and 

 becoming shorter and more rhomboidal near the margin. 



The material from Gilkerson's Ford contains many detached pinnules 

 of a ''JDictyopteris''' which I at first thought might be a variety of one of the 

 species already described; but a comparison with the literature and speci- 

 mens representing the described American species leaves little doubt as to 



• Can. Rec. Sci., vol. iv, 1890, p. 8. 



