
596 The American Naturalist. [July, 
remarkable contributions to paleontology ever published. Criti- 
cism can, of course, be based only upon the published diagnoses, 
descriptions, and figures in comparison with our present general 
knowledge of these early mammals. Other evidence is promised 
by the author, and I venture to predict that it will confirm the 
greater part of the conclusions reached in this review. 
First, as to extent and general character. The conspectus of 
the author impresses us that this fauna is not only highly varied, 
but contains forms which are mostly new to science. Four orders 
are believed to be represented: the Allotheria, Pantotheria, Mar- 
supialia, and Insectivora. The author finds six families among the 
Allotheria alone, four of which are new; five new families in all. 
Sixteen new genera and twenty-seven new species are described. 
All of the types are isolated teeth, excepting those of Camptomus. 
With the exception of Halodon, Cimolomys, and Dipriodon, only 
one tooth of each species is described,—-~z. e., from different parts of 
the jaws,—and we are given to understand that the remaining 
teeth, found with each, will be described in the memoir now in 
preparation by the writer, under the auspices of the United States 
Geological Survey. 
Before this varied fauna is generally adopted in paleontological 
literature, let us examine the author’s types and diagnoses, keeping 
in mind some of the characteristics of his work. These are: 
First, as regards other authors, not fully recognizing priority of 
discovery and nomenclature. Second, not taking advantage of 
_ readily available previous literature and description. Third, fail- 
ing to recognize well-determined morphological characters, and 
founding extensive taxonomic systems upon “various portions of 
the same animal, or upon imperfectly characterized types. The 
very fact that this work is done under the auspices and with the 
support of the National Survey renders it the more necessary to 
subject it to a full and fair spirited criticism ; for the first char- 
acteristic of such work should be, not opens: but permanent 
value. 
Priority of Discovery and Nomenclature.—lIt is evident that the 
„same fact cannot be discovered twice, in case the original dis- 
= covery is authentic and properly published. It is well known 



