FEENS— INCERT.E SEDIS— APHLEBIA. HI 



Weiss, from Saarbruck, and especially to those so aclmirablv delineated by 

 Kidston from the specimen from the Radstock coal field.^ In fact, so far 

 does the specimen from Missouri agree with the example from Pucklechurch 

 that the differences ranj almost be accoimted for as coming within the mod- 

 ifications of different portions of the same plant or as individual variation. 

 The American, like the British, specimen is membranaceous; the lateral 

 pinnfe are similar in form and position, connate and very decurrent; the 

 lobules oblique, alternate, connate, decurrent, each being traversed by a 

 single distinct nerve; the midribs of the pinnae, too, are curved near the 

 base and pass down a long distance before joining the main rachis. It is 

 probable, also, that the lower lobules may become bifid. But our fragment, 

 which seems to correspond in size, position, and development with the 

 specimens both from the Radstock field and from Saarbruck, differs, as will 

 be seen from the illustrations, from that figured by Kidston by the much 

 broader dilated nerves and midribs of the lateral pinnae, the obtuse lobules, 

 which are considerably larger and recurved, while none of them are yet 

 bifid, and the more narrowly acute sinuses at the bases of the pinnse. 

 Nevertheless, the difi^erences between the British and the American plants 

 are of such ixiinor rank and importance as to seem to justify at most no 

 greater distinction than a varietal separation, if any. 



On the other hand, the points of difference between the fragment from 

 Missouri and that from Saai'bruck, to which Weiss gave the name of Bha- 

 cophyllum GoIdenbergU, are obvious frofn a comparison of the figure given 

 by Schimper. The latter has not even the appearance of being membra- 

 naceous, and is not so described. In the American specimen the pinnae are 

 broader and much more constricted, relatively, at the base, the lobes not so 

 erect and straight, not narrowly slender and tapering and acute. Schimper 

 does not describe the nervation, and the figure seems to indicate a thick 

 and rather coriaceous lamina in which either the nervation is not very clear 

 or it is diftuse. 



Notwithstanding, therefore, the high degree of variation known to exist 

 in the species of AjMebia, even in different portions of the same individual, 

 it has not seemed to me to be proper to record our specimen in the same 

 species with that from Saarbruck. I have, accordingly, ventured to assign 



1 Foss. Fl. Eadstock Series, pi. xxvii, fig. 2, p. 388. 



