Othniel Charles Marsh. 19 
issued in 1886 by the United States Geological Survey. His 
work in other groups of mammals is scattered through a large 
number of separate papers, and contributions were made to 
every known order. The Tillodontia comprise one of the 
most remarkable of the types. Among others are the first 
remains of fossil Primates, Cheiroptera, and Marsupialia, 
known from North America. The Brontotheride and 
Coryphodontia received considerable attention. A monograph 
had been begun on the former, and restorations of a typical 
genus of each were published. 
One general conclusion of much significance was the out- 
come of his researches on the Mammals. It was that the 
Tertiary genera possessed very small brains. As a single 
example, Dinoceras may be taken. This animal was but 
little inferior to the elephant in bulk, but its brain capacity 
was not more than one-eighth that of existing rhinoceroses. 
The first Mesozoic Mammal in America was described by 
Emmons, in 1857, from the Triassic of North Carolina. 
Marsh, by his extensive discoveries, was enabled to fill up the 
gaps to the Tertiary with many genera and species from the 
western Jurassic and Cretaceous. Probably nine-tenths of all 
the Mesozoic Mammals known in the world were described by 
him, and while these remains are of great interest, yet from 
their fragmentary condition they are not of the highest scien- 
tific value, because little is known beyond the jaws and a few 
limb bones. 
In closing the outline of the discoveries made by this inves- 
tigator, one cannot help being impressed with their signal 
brilliancy, their great number, and especially by their unique 
importance in the field of organic evolution. Were all other 
evidence lost or wanting, the law of evolution would still have 
a firm foundation in incontrovertible fact. The study of 
variation and embryology in recent animals gives hints as to 
the truth, but Paleontology alone can give the facts of descent. 
CHARLES E. BEEcHER. 
YALE UNIVERSITY MUSEUM, 
New HAVEN, CONN., May Ist, 1899. 
