INTRODUCTION. 



ON THE GENERAL SIGNIFICANCE OF THE SCIENCE OF 



PALEONTOLOGY. 



I. 



Paleontology is an exact science. It embraces generalizations or laws 

 obtained by induction, which may be deductively applied to the unknown. 

 Its first law is an illustration of the uniformity of nature's methods, namely, 

 the law of the persistence of type. An organized structure once created, 

 and existing under circumstances not hostile to its working, is adhered to 

 with the greatest fidelity, and extended in time and space. This constant law 

 is the key to this as to the other biological sciences, and occasionally surprises 

 the student of evolutionistic proclivities. On this basis, the possibility of 

 reconstruction of the extinct forms of the past will always rest ; and the cer- 

 tainty of the law is unconsciously admitted by every paleontologist who 

 determines, names, or classifies a fossil from anything less than a perfect 

 specimen. It is assumed every day, and universally allowed, although occa- 

 sionally even an expert is found who sometimes questions it, and still more 

 frequently an inexpert who does not read nature aright. 



The application of the law is, however, various as the given terms, i. e., 

 the remains presei-ved, differ in significance. Thus, to illustrate, certain parts 

 are common to all stoves, and distinguish them from all other articles of furni- 

 ture ; but certain other parts not only belong to a stove, but mark a given 

 pattern of stove, since they belong only to it. A still more minute range of 

 appearances is found only in one man's make of stoves, and others in that of 

 another man. Hence, a person acquainted with stoves, sewing-machines, 

 &c, can readily determine the origin of a very small part by referring it to its 

 proper kind and make. 



The application of this law of persistence presupposes a knowledge of 

 the pattern as essential to its deductive application. Hence, a difficulty at 

 once suggests itself as arising when a portion of an animal belonging to a new 



