528 PROCEEDINGS OF THE ACADEMY OF [1897. 



ogous. It illustrates bis constant aim to establish some other, and 

 if possible more stable, criteria of cranial comparison than those in 

 common use ; and, on the other hand, to subject the latter to a 

 much closer criticism than they have heretofore received. 



In the former direction he emphasizes the significance of the 

 presence of the prenasal fossa as determining grade ; points out the 

 value of the infraorbital suture, which is generally neglected ; and 

 offers as entirely new the comparisons of the pyramidal process of 

 the palatal bone and the prominence or recession of the zygoma 

 when the skull is viewed from above. He estimates with precision 

 the signification of pedomorphism as a sign not so much of arrested 

 as of incompleted development. 



One of the most striking results reached is, in his own words, 

 that " the differences between the crania are not due to race, but to 

 methods of living, and in some degree to differences of mental 

 strength in individuals." This modest statement by no means con- 

 veys the full import of his demonstration. What his laborious, 

 skilful, and accurate measurements show, taken in conjunction with 

 the proved unity of race but diversity of nutrition and culture- 

 conditions of his specimens, is that the ordinary contrasts in skull- 

 forms, upon which many stately theories of races and schemes of 

 prehistoric interminglings have been erected, are of such doubtful 

 significance that they are inadequate for that purpose. 



Pursuing this line of research further, Dr. Allen asked himself, 

 what is the proximate and remote etiology, what are the immediate 

 and more distant factors in the modification of skull forms? In 

 this memoir he brings out some of these with force, while others 

 which, had he lived, he would have developed fully, are merely 

 suggested. Thus, the correlation of the loss of the upper front 

 teeth with important variations in cranial conformation is admira- 

 bly set forth ; and the influence of diseased action causing disuse, 

 and thus, in turn, lessening nutrition and modifying shape and con- 

 tour, is clearly explained. 



Some inquiries which he advanced tentatively were of far more 

 weight in his own mind than his expressions indicate. For exam- 

 ple, in the last conversation I had with him, a few days before his 

 decease, he asked my attention particularly to the consideration 

 whether the whole range of exanthemata, and especially measles, to 

 which the white race has been time out of mind exposed and is now 

 largely immune, are not chargeable with many of its peculiar char- 



