OBJECTIONS AND DIFFICULTIES AXI) OTHER THEORIES 227 



Conclusion (Od><>,-// ). 



It must not lie understood by the reader that the author of this 

 volume is doggedly maintaining a theory of the origin of the upper 

 molars, in which he has had a part, simply from personal reasons. 

 On the contrary he believes the question to be still .s/'fr jiulice and 

 will be the first to acknowledge his error if error it prove to be. 



The author moreover feels the full force of the very strong evidence 

 arrayed against the Cope-Osborn view. The evolution of the upper 

 molars is certainly not so simple as it at first appeared. It was 

 never maintained by Osborn, as is proven in his full series of 

 papers here reproduced, 1 that the molar of Triconodon (Fig. 11 a), 

 gave rise to that of Dryolestcs (Figs. 206, 207, Nos. 2, 3), or even 

 that all mammals passed fully into a triconodont stage, such as that 

 of Ainphilestes (Fig. 5). The starting point of the superior molars 

 was supposed to be an extremely primitive triconodont type either 

 with the cusps in line or with the pattern of molars of the 

 Spalacotherium (Fig. 11) type inverted as shown in Peralestes (Fig. 12). 



pp. 8, 33. 



