184 THE AMEBIC AN NATURALIST [Vol. XL VII 



definite ones between the smaller groups of many vertebrates 

 but not between the larger ones. Many writers, especially writ- 

 ers of text-books, assume much more than they can prove, and 

 the great majority of the modern zoological text-books are sadly 

 behind the times in matters of paleontological knowledge and 

 works that serve as standards and bases for the construction of 

 more elementary texts make the most bald misstatement of 



The general trend of paleontological research is to round out 

 our knowledge of the diversity and structure of many groups; 

 the establishment of a few new groups especially of lower rank ; 

 no one save Jaekel having had the temerity to propose new 

 groups higher than sub-classes. 



Not all of the recent work in vertebrate paleontology is 

 reviewed here. Many excellent works have been sufficiently 

 noted elsewhere but sufficient is here given to show the tendency 

 of thought and work among the vertebrate paleontologists ; that 

 of attention to matters of structure, occurrence, association, 

 interpretation of matters of organization and relationship, all 

 of which are fundamental to safe conclusions regarding the 

 larger problems of phylogeny. It is perhaps too early to arrive 

 at such conclusions in regard to phylogeny as we should wish 

 to have — but paleontology is 100 years old and more ! 



One of the more recent puhlicatious from the press of Gustav 

 Fischer is a volume entitled " Die Abstammungslehre," a col- 

 lection of twelve essays on the descent theory in the light of 

 recent researches. The ninth essay is one by Dr. 0. Abel, in 

 which he discusses "Die Bedeutung der fossilen Wirbelthiere 

 fur die Abstammungslehre." Dr. Abel says there were two 

 ways in which he might discuss his subject, either by giving a 

 short resume of the investigations of paleontologists or by dis- 

 cussing the methods of paleontological investigation and the 

 bearing of the results of these methods on the descent theory. 

 He has chosen the latter and has discussed his subject in a 

 masterly manner. He has divided his paper into three parts 

 with various sub-headings and discusses a phase of paleonto- 

 logical methods in each division. He discusses the alleged lack 

 of material among paleontological specimens and shows that, 

 in a few instances at least, there is more material available for 

 study of the forms than there is for many of the recent species. 

 The discussion of the value of reconstructions in paleontology 



