PALEONTOLOGY, ITS AIMS AND METHOD 213 



dominantly held by men who were primarily stratigraphers, 

 using their fossils merely as dating objects for the rocks in 

 which they are found. The latter form of study had, until 

 recently, no philosophical background; it was purely empirical, 

 arguing solely from observed occurrences of individual types 

 whose history was not only unknown but not even inquired 

 into. 



The morphological side of palaeontology very rapidly 

 acquired a distinct meaning ; in the hands of Owen it was 

 used to support, and to be in its turn assisted by, the " Arche- 

 typal theory." By the use of this theory, which unconsciously 

 at first, but knowingly in its later and degenerate days, was 

 distinctly evolutionary in its outlook, Owen was led to the 

 correct appreciation of many homologies, to the distinction 

 between homologous and analogous structures, and to an 

 understanding of relationships which is often so accurate and 

 so in advance of his time as to be uncanny. 



The coming of evolution and its general acceptance gave 

 a new meaning and a new interest to the many facts collected 

 by Owen in relation to his archetypal theory ; they fell at once 

 into place as the evident result of evolution, whatever its 

 method. 



The first palaeontologist to adopt a definitely evolutionary 

 outlook in his work was A. Gaudry ; but the full development 

 of a philosophical method based on the fact that every organism 

 is the modified descendant of a long line of ancestors was due 

 to W. Kovalewsky, Professor of Palaeontology in Moscow, who 

 by this great achievement established an irrefragable claim 

 to be called the second founder of this science. 



Reduced to its ultimate terms the method of Kovalewsky 

 is this : — Palaeontological material to be valuable must be of 

 a special kind ; it must consist of a series of forms which either 

 actually stand to one another in the relation of parent and 

 child or are close blood relations belonging to different genera- 

 tions. Direct comparison of such forms with one another 

 will show differences which may be due either to the fact that 

 the animals compared are not really parent and child or to 

 the evolutionary change which has taken place between the 

 generations studied. It is the business of the student to 

 discover the real direction of the evolution and finally to sum 

 up his work by the construction of a genealogical tree. 



