4 Othniel Charles Marsh. 
‘it was impossible for him to do more than seize on what 
appealed to him as the most salient. The work of the hour 
was to him of prime importance, whether it was for the deter- 
mination of a new order of mammals or a new cusp on a 
tooth. Still, he seems to have had a just conception of relative 
values, for it will be found that he plucked the most luscious 
plums from the paleontological tree, and left chiefly the smaller 
or unripe and imperfect fruit untouched. 
Another element in his success was seen in the improve- 
ment he made in the methods of collecting, preserving, and 
developing vertebrate fossils, so that even forms long known 
only from fragmentary remains were represented in his collec- 
tions by almost complete specimens, presenting nearly the 
same degree of novelty shown in forms actually new. 
In illustration of this, the Brontotheride, Ceratopsia, and 
the Mosasauria furnish excellent examples. Prout, in 1846, 
described, as Palwothervum, the fragment of a lower jaw from 
the Miocene of Nebraska, but Marsh first showed the affinities 
and range of forms in the group, through his splendid restora- 
tion of Brontops and the description of a number of allied 
types from nearly perfect material. Cope, in 1875, figured 
some pieces of bone of unknown relationships, which long 
remained in the paleontological scrap-basket.* Marsh, by his 
descriptions of the marvelous series of genera and species 
belonging to the Ceratopsia, demonstrated what these reptiles 
really were, and gave to science a nearly complete knowledge 
of one of the most bizarre monsters known. The first 
Mosasaur was obtained in Holland previous to 1785. ‘It 
remained imperfectly known for nearly a century, when Marsh, 
by his contributions to its anatomy, made possible a clear 
understanding of its structure and affinities. In the same way 
it could be shown that to many old descriptions of genera and 
species based upon single teeth, he was enabled to add a 
knowledge of the remainder of the animal. Not only did he 
thus contribute the missing information in regard to many 
previously described forms, but he brought out a host of 
entirely new types, and made his science one of the most com- 
plete exponents of the doctrine of evolution. 
* Polyonax. 

