500 STUDIES FOR STUDENTS 
taxonomy of the subject or to the faunal relationships of the 
fossils described. Such work, however, is valuable even today in 
so far as it is accurately done, because it relieves the investigator 
in the more special lines of research from a vast amount of 
labor. Every species of fossil must have a name as a sort of 
handle by which it may be manipulated, but with the more spe- 
cial workers in the subject, the description of species and the 
giving of names is but a means to an end, the discovery of new 
species not being the ultimate result sought after. 
The biologic division of paleontology consists of the study 
of the structure and organization of individuals, of their ontoge- 
netic development, of the relationship pf species to species and 
of genera to genera, and of their phylogeny, all with the ultimate 
end of establishing as nearly as possible a natural classification of 
all organisms. A large proportion of all the work being done 
today among fossil vertebrates comes into this category. Among 
the invertebrates much work of a high order is also being 
accomplished. The recent contributions by Beecher upon the 
structure, ontogeny, and classification of trilobites and of brach- 
iopods may be mentioned, also the contributions by Hyatt and 
others upon the cephalopods. 
The faunal study of fossils is intimately connected with geol- 
ogy, in fact no history of the earth, from the period beginning 
with Cambrian time, can be made complete when the life history 
is excluded, and for this reason this faunal study of fossils is 
coming to be called paleontologic geology. Instead of taking 
a single species or any taxonomic group as the unit of study, as 
is done by the biologist, organic societies, those organisms which 
lived in a single locality under similar environment during a lim- 
ited period of time, are the subjects of investigation. The fossil 
societies or faunas are dissected into their various elements, their 
relation to the environment in which they existed are studied, 
their relations to neighboring societies or faunas, both in time 
and space, and their migrations are the subjects of investigation. 
The study is a history of organisms in its broadest sense, and it 
is just as truly an historical study as is the study of human his- 
