46 FLOEA OF LOWER COAL MEASURES OF MISSOURI. 



referred by Professor Lesquereux to Splienoi)teris tridactylites Brougn. 

 From the latter, liowever, so far as that species is illustrated and described 

 in foreign literature, Hymenophyllites liinnatifidiis differs very much, the 

 analogies being much closer to Spheno])teris delicatula Brongn. as figured 

 by Sauveur,^ Trichomanites (Zeilleria) delicatida illustrated by von Roehl,^ 

 or the Sphenopteris (JSapalopteris) Schiitsei Stur, represented b}" Kidston in 

 the flora from the Lanarkshire coal field.^ 



In PI. XIX, Fig. 1, is shown a photograph of a portion of the original 

 of figs. 9 and 9fl-&, on pi. Iv, of the Coal Flora, referred to Splienopteris 

 tridactylites Brongn. The enlarged detail, Fig. la, PI. XIX, of the sterile 

 pinna in this specimen (No. 4304 of the Lacoe collection), which comes 

 from the same locality as the other specimens before me, and represents 

 precisely the same form, shows the great difference in proportions between 

 S. pinnatifida and the original type of the species of which it was made a 

 synonym. 



Fig. 9 in the plate of the Coal Flora includes only the middle one of 

 tln'ee compound pinnte borne on the right of a somewhat flexuous rachis 

 3 mm. in width. Portions of alternately placed pinuije on the other side are 

 also fertile. Although the laminae or margins of the divisions of the pinnule 

 are obscure in the fertile frond, even where the sporangia are absent in the 

 lower part of the pinna, enough is clear to show that the form of the sterile 

 pinnules on the same pinna is the same as in the sterile pinna by its side. 

 Fig. 9« of the Coal Flora, which seems to agree with fig. 8a of the same 

 plate,' fails to show either the real character of the division of the pinnule or 

 the open angles and space between the lobes, which are very delicate. 



The sporangia seem to present the general aspect shown on the right 

 in Lesquereux's fig. 9fl, though they are not so round. Under the lens 

 they appear to have a structure like that shown in the genus Urnatopteris 

 of Kidston,'' which, in certain specimens less compressed, ours seems to 

 resemble in ovoid form and apical pore. But Urnatopteris lias the sporangia 

 iu two rows, one on each side of the nerve of the lobe, while in Splienopteris 

 pinnatifida the sporangia seem to be in irregular groups. This compact group- 



' V(5g. foss. terr. houill. Belg., pi. xxiii, fig. .5. 

 -Foss. Fl. Steink. WuBtplialeus, p. 6S, pi. xvi, fig. 6b. 

 'Pl.iii, fig..5. 



^Qnart. Jour. Geol. Soc, vol. xl, 188-1. p. 494. 'Zeiller, Fl. foss. houill. Valenciennes, 1888, p. 

 33, fig. 20. 



