GASTEEOPODS. 203 



Genus Bulimorpha WHITFIELD. 



In addition to those species originally included Bulimor- 

 pha has recently been found to embrace several described 

 forms long known under other generic titles. The group was 

 first designated as Buliinella by Hall, but this name was pre- 

 occupied by Pfeiffer. Eecognizing that Hall's name could not 

 be retained, Meek and Worthen, who, in 1866, had just intro- 

 duced Portlock's term Polyphemopsis into the literature of 

 American Paleontology, referred to the genus the species 

 described by Hall under Bulimella, and also three additional 

 forms, originally placed with Loxonema and Bulima. A num- 

 ber of other American fossil gasteropods have from time to 

 time been assigned to Portlock's genus. But Polyphemopsis 

 was founded on very imperfect material, and its structural 

 characters have never been sufficiently understood to definitely 

 limit the group. It seems to be regarded by the majority of 

 European writers as a synonym of Macrochilus Philips. The 

 latter, however, has recently been shown to be identical with 

 Soleniscus Meek and Worthen, which has precedence over 

 Phillip's preoccupied term. 



Although more than half a score of species have, in this 

 country, been referred to the genus, it is quite apparent that 

 members of at least two very different groups were included ; 

 while a detailed comparison of the various representatives 

 appears to indicate that, with a few possible exceptions, 

 no forms congeneric with Portlock's Polyphemopsis elongata, 

 which may be regarded as the type of his genus, have as yet 

 been recognized, with any degree of certainty, in the Paleozoic 

 rocks of America. Until typical specimens of Polyphemopsis 

 can be critically examined, the genus must be considered as of 

 very doubtful utility. 



As already stated, there were embraced in this group such 

 species as constituted Hall's genus Bulimella. These, perhaps, 

 best exemplify the American forms of the section under con- 

 sideration. The shells are fusiform, with the spire elongated ; 

 the whorls more or less decidedly convex, the last rather large ; 



