14 
advance in the record, higher types maice their appearance This 
will be seen and understood by reference to the tables of Life 
Records, Figs. 3 to 7, on pages 16-20, copied from Dana 's Manual 
of Geology. 
CLASSIFICATION OF FOSSILS. 
Scientific Names. — Objects of Natural History are of such 
general interest to all civilized people, that it long ago became 
necessary to designate them by name, that they might be spoken 
of or written about understandingly, and be recognized by people 
of different countries and tongues without confusion : this 
required that the names should conform to some fixed plan. 
Previous to the time of Linnasus (about the middle of the 18th 
century) common names or descriptive sentences were usually 
applied. These were often so long and complicated as to be un- 
intelligible or very cumbersome. To avoid this, Linnseus proposed 
to use a binomial (double name) system, constructed of Latin or 
Greek words ; these languages being commonly understood by 
scholars in all countries. This plan has been universally adopted 
by all writers, with an additional precaution of never applying the 
same name to different objects within the same sub-kingdom. In 
this way has arisen a system of classification, composed of a series 
of names which are applied to groups of animals or plants of 
greater or less value, but which recognizes the relations and 
affinities which one animal or plant bears to another, depending 
principally on their structure and the perfection of their various 
organs in their adaptability to the purposes of life. These divisions 
are : first Species, individuals of the same kind ; then Genera, 
Families, Orders, Classes, Provinces and Sub-kingdoms. 
The use of some such classification is indispensable in arrang- 
ing collections of fossils to illustrate geological history. The 
classification used in this collection is first Geological, according 
to epochs, and under this, according to Lithological areas 
(mineral composition of the rock), which is also to some extent 
geographical. Under each of these divisions there is an indepen- 
dent Zoological classification of the fossils, passing from the 
lowest to the highest , that is, according to their zoological affini- 
ties, which is found to be nearly in their order of appearance in 
geological time. 
