Contributions to Paleontology. 369 
the merit of the work: there ne indeed few hag have exhibited 
in their labors such sagacity the forming of the smaller 
groups, among Mollusca, and ae spiptenianin of nny affinities, 
as Mr. Conrad. 
The Miocene, commencing along our eastern border at Mary- 
land, extends southward to South Carolina, and on the western 
border, it is developed in California and rt while in Dako- 
ta, fresh-water deposits have been referred to that period; it is 
not, however, by any means certain that these several deposits 
are sy nchronous.* ‘In the east, the southern extension of the 
strata has been referred to the Pliocene, but it is traceable into 
ge! assis} and Muricide re Mfaniciden, Bueciniie ba ‘Tn the 
i cl 
pecially 7. altclis and Bulliopsis; the latter group has hs ot d 
in the Vienna Basin, &., which have been referred to 
Melanopsis. But the consideration of such Kee ould tran- 
scend the limits of a review. Before closing, we would, how- 
ever, refer to some b sdessedeescrn: features exhibited in the ‘publi- 
cations hate noti 
rely ses" in paleontological publications, and yet ex- 
tranely- Selec is the indication by the authors of the sup- 
posed ‘affinities of all the deen atedtedt by them into the 
system. ‘This contrasts most eine with the negligence in 
was like. Such race tions, moreover, are ‘ended with characters 
prey family, ordinal, or even classical, and partly specific com- 
inations, which e ile ently indicate that the authors had no clear 
idea of the mre of the forms introduced; nevertheless it 
were to be desired that knowledge and het in this respect 
could be exacted. Akin to this 1 is the custo when hints are of- 
as “connecting links” between representatives of widely ditties 
ent groups. Without mii. to any known si rior 
1 tay be tes eect hat the fc 
to the Miocene by Mr. Conrad, are now considered bet him to be of ae 
tiid ehicanecnsed Me hie tot they are also — ate i cae 
species, an and finally, Dr. Ca nter has identifie 
living forms. It is more feitain that Dr. C Carpenter & yee Se aoe tr he iden. 
tilationse sha ties ee Mr. Conrad was not right in the first instance. 
