62 FLOEA OF LOWER COAL MEASURES OF MISSOURI. 



twenty years ago by Professor Lesqiiereux under tlie name Sorodachis opliio- 

 (jlossoides} The extremely close relationship of the sterile pimise from 

 Missouri with others from Mazon Creek, Illinois, which the unpublished 

 manusci'ipt and di-awing-s of Professor Lesquereux show in direct connec- 

 tion with Sorocladus sagUtatus Lx.,^ the identity of structure which on exam- 

 ination of the t}'pe specimens I find to exist between Sorocladus opMoglossoides 

 and Sorocladus sagittatus, and the surprising and impressive analog}' of both 

 the fertile and the sterile segments of the American sjiecies to the corres- 

 ponding portions of Sphenopteris Boidayi ZeilL, and Splienopteris Crejnni 

 Zeill., from the Valenciennes basin, place beyond doubt the relationship of 

 the sterile fragments from Missouri to the group represented by Sorocladus 

 sagittatus Lx. And since the remarkable affinities between the Missouri 

 and the Illinois sterile forms compel us to expect a fertile pinna for the 

 Missom-i species very similar to that described from the other State, we can 

 hardly avoid the conclusion that Sorocladus opMoglossoides, which completely 

 satisfies these conditions and fulfills the analogies, is really the fertile por- 

 tion of the species to which the fragment illustrated in PL XX, Figs. 3, 4, 

 which comes from the same region, belongs. 



It would manifestly be unjust to anticipate the publication of any 

 data included in the manuscript report of Professor Lesquereux, however 

 interesting might be the comparison of the details therein contained. 

 Consequentl}" no further reference will be made to the sterile specimens 

 from Illinois. 



The Missouri specimens before me are specially characterized by the 

 irregular appearance of the sui-face of the pinufe, the system of crenulate 

 lobation, and the ragged aspect of the nervation, which appears fasciculate 

 at the base of the lobes, and arches strongly iipward. 



The types of Sorocladus opliioglossoides Lx., from Hem-y Count}-, now 

 in the Lacoe collection (Nos. 4170-4172) in the United States National 

 Museum, bear a very striking and interesting- resemblance in their form, in 

 the characters of the fleshy lamina, and the fringe of sporangia about the 

 latter, suggesting, as Zeiller remarks, fringed epaulets, and even in the 

 superficial characters of the sporangia, to the t}-pe of Sphtnopteris Boulagi 



' Coal Flora, vol. i, p. 329, pi. xlviii, fig. 11. 



■ Coal Flora, vol. i, p. 329, pi. xlviii, figs. 10-106 ; vol. iii, p. 760, pi. c, figs, i, 5. Through a uiisun- 

 derstandiug a very incomplete drawing of one of the specimens examined by Professor Lesquereux 

 was included in Lesley's Diet. Foss. Pennsylvania, vol. ii, p. 606. 



