2 PRINCIPLES OF PALZZAONTOLOGY. 
prehend the former, unless we possess some knowledge of the 
latter. However great its physical advances may be, Geology 
remains imperfect till it is wedded with Palzeontology,* a study 
which essentially belongs to the vast complex of the Biologi- 
cal Sciences, but at the same time has its strictly geological 
side. Dealing, as it does, wholly with the consideration of 
such living beings as do not belong exclusively to the present 
order of things, Paleontology is, in reality, a branch of Natu- 
ral History, and may be regarded as substantially the Zoology 
and Botany of the past. It is the ancient life-history of the 
earth, as revealed to us by the labours of palzontologists, 
with which we have mainly to do here; but before entering 
upon this, there are some general questions, affecting Geology 
and Paleontology alike, which may be very briefly discussed. 
‘The working geologist, dealing in the main with purely phy- 
sical problems, has for his object to determine the material 
structure of the earth, and to investigate, as far as may be, the 
long chain of causes of which that structure is the ultimate re- 
sult. No wider or more extended field of inquiry could be 
found ; but philosophical geology is not content with this. At 
all the confines of his science, the transcendental geologist 
finds himself confronted with some of the most stupendous 
problems which have ever engaged the restless intellect of 
humanity. The origin and primeval constitution of the terres- 
trial globe, the laws of geologic action through long ages of 
vicissitude and development, the origin of life, the nature and 
source of the myriad complexities of living beings, the advent 
of man, possibly even the future history of the earth, are 
amongst the questions with which the geologist has to grapple 
in his higher capacity. 
These are problems which have occupied the attention of 
philosophers in every age of the world, and in periods long 
antecedent to the existence of a science of geology. The mere 
existence of cosmogonies in the religion of almost every nation, 
both ancient and modern, is a sufficient proof of the eager de- 
sire of the human mind to know something of the origin of the 
earth on which we tread. Every human being who has gazed 
on the vast panorama of the universe, though it may have been 
but with the eyes of a child, has felt the longing to solve, how- 
ever imperfectly, “the riddle of the painful earth,” and has, 
consciously or unconsciously, elaborated some sort of a theory 
as to the why and wherefore of what he sees. Apart from the 
profound and perhaps inscrutable problems which lie at the 
bottom of human existence, men have in all ages invented 
* Gr. palaios, ancient ; onta, beings ; Jogos, discourse. 
