126 FLORA OF LOWER COAL MEASURES OF MISSOURL 



segment of Neuroptevoid limb, such as is not unconnnon in Neuropteris or 

 Odontopteris^ sublobate at the top and succeeded by several obtusely pointed 

 or obtuse, decun-ent, more or less ovate and obovate pinnules, extending up 

 to the lanceolate obtuse terminal. On the lower right are several ovate- 

 ti'iangular acute pinnules with broad decurrent attachments, the lower ones 

 auriculate, succeeded above by pinnules similar to those alternating on the 

 other side. The nerves are rather thick and fairly distinct, though the 

 lamina is moderately thick. The nervation of the large segment is close, 

 Neuropteroid, arching to meet the apex at a right angle. That of the other 

 pinnules is essentially flabellate and Odontopteroid, the nerves entering by 

 the whole width of the attachment of the pinnule and curving somewhat 

 toward the margin, where they turn slightly upward. A coarse strand, 

 passing from a little below the sinus on the upper side of the base of the 

 pinnule to the apex, supplies the nervils for the upper side of that pinnule. 



Although this fragment appears undoubtedly to belong to the group 

 of heteromorphous species represented typically in Odontopiteris Wortheni 

 Lx., 0. stibcimeata Bunb., 0. cornuta Lx., 0. deformafa Lx., and 0. Bradleyi 

 Lx., its identity with any of them is questionable. The four of these 

 species first named and 0. affinis Lx. all may, and do in some of the 

 examples identified by the author of those species, have large basal seg- 

 ments on one or both, sides of the axis. But while strongly resembling 

 especially the 0. Wortheni or 0. sidjcwneata Bunb. by the large basal lobe 

 and the terminal portions, the pinnules of these species are characteristically 

 obtuse, the upper ones being obovate-cuneate ; and in all examples except 

 a single individual (No. 384 of the Lacoe collection) from Mazon Creek, 

 Illinois, in the United States National Museum, identified by Professor 

 Lesquereux us 0. WortJieni, the nervation is coarser and much more distant 

 than in our si)ecimen. 



Odordopteris Bradleyi Lx., with which the specimen is temporarily left, 

 is an ambiguous species which was first described from a small fragment 

 of a single pinnule. But one of the specimens in the Lacoe collection 

 (No. 1256), examined and identified by Lesquereux prior to the publication 

 of the Coal Flora, is a segment of a pinna in which the pinnules have 

 nearly the same characters as in our specimen, except that they are much 

 more constricted at the base, with finer nervation, while the rachis is less 

 lax. Nevertheless, no large basal lobes are present in this specimen. It 



