720 General Notes. (August, 
To the American paleontologist the greatest value of this 
memoir consists in its descriptions and inferences as to the his- 
tory of the Artiodactyla. The materials for this study are more 
limited in America than in Europe. 
Dr. Schlosser gives full credit to work done and conclusions 
reached in America. He adopts the views here proposed as to 
the ancestral position of the Condylarthra; and also the theory 
of the phylogenies of the teeth and feet of Mammalia proposed 
by Cope. The only defect in knowledge of American literature 
we observe, is the case of the report on the vertebrate palzon- 
tology of Colorado, published in the Annual Report of the U.S. 
Geol. Survey of the Terrs. for 1873. On this account the char- 
` acters of some genera are overlooked. i 
“here are some positions adopted by the author which we sus- 
pect that he will modify. Thus his systematic views are different 
from those which have been usually held, in that he uses phylo- 
genetic series as identical with taxonomic divisions, and not, so to 
family which are given (p. 33) are not true of Hyracotherium. 
_ Although there can be no doubt that this genus is the ancestor 
of Equus, all taxonomic precision requires that it s ould e 
placed in a distinct family from that genus, and in company Wit 
_ genera (e. g., Systemodon) which Dr. Schlosser places (p. 27) in 
-his Tapiridæ. To illustrate this matter more precisely I e 
__ the phylogeny of Equus arranged in the family phases throug 
which it has, in my opinion, passed, and as I have given it: 
Equus belonging to Equide 
| 
Protohippus, éte | i; 
Anchitherium \ Palzotheriide 
Lambdotherium “ Chalicotheriidæ 
| 
