ANATOMICAL STRUCTURE OF ANTHROPOID APES. Ill 



frontal bone. One of the most common disturbances 

 in the symmetry of the connecting suture, as we 

 have already briefly mentioned, arises from the 

 insertion of a frontal process of the squamous portion 

 of the temporal bone between the lower angle of 

 the parietal bone, the fore-part of the frontal bone, 

 and the greater wing of the sphenoid bone. This 

 process of the, temporal bone varies in size, and may 

 occur on one or both sides. A similar formation is 

 common among gorillas, chimpanzees, macacas, 

 magots (Inuus), and baboons.* It is less frequent 

 among orangs,t gibbons, marmosets, and American 

 species (howlers, hooded apes, etc.). 



Virchow and W. Gruber have agreed in repre- 

 senting this frontal process as theromorphological — 

 that is, as a characteristic of the lower animals, and 

 more especially of apes. Virchow has found this 

 abnormal formation of the skull to be more com- 

 mon in some races than others. None of those in 

 whom it occurs appear to belong to the Aryan 

 races, and the existence of this process and steno- 

 crotaphy, or temporal stenosis, seem to be due to a 

 defective development of the greater wing of the 

 sphenoid bone, and to the compression of the bones 

 in its vicinity, by which the whole temporal region 

 is contracted. This is a characteristic of the lower, 

 but by no means of the lowest, races of men. 



Stieda, Hyrtl, Gruber, and Calori have sought to 



* It appears to be very oommoii among Japanese apes (Inuua 

 speciosus). 



t Briiil has noted the intermittent occurrence of a connection 

 between the greater wing of the sphenoid bone and the temporal 

 bone. 



