LECTURE III. 81 



that both sexes would not be included in the same genus, much 

 less in the same species, if their relations to each other were 

 not ascertained. It would have occurred to no naturalist to 

 associate the beautifully decorated cock pheasant or peacock 

 with their plainer mates, if their sexual relations were not 

 known, and I might quote hundreds of instances occurring 

 among mammals and the anthropoid apes, in which sufficient 

 sexual differences occur to justify their arrangement in dif- 

 ferent species. Thus it is with the orang, the baboon, howling 

 monkey, and other apes, more or less approaching man in struc- 

 ture. When, therefore, Welcker justly observes, that the skulls 

 of man and woman are to be separated, as if they belonged to 

 two different species, and that they differ in their proportions 

 more than many typical or race skulls, he gives expression to a 

 fact in nowise peculiar to the human species, but one that finds 

 its counterpart in the mammaha, and especially in the anthropoid 

 apes. According to Welcker, the female skull is smaller, both 

 as regards horizontal circumference and internal capacity, and 

 the weight of the brain corresponds with this. The female 

 skull exhibits, according to Welcker's measurements, the fol- 

 lowing proportions, assuming the male =100 throughout: — 

 circumference = 96-6; capacity = 89-7; weight of brain = 89-9. 

 The outlines of the female head are rounder; the facial portion 

 of the skull, especially the jaws and the base of the skull, 

 smaller, the latter being especially narrower in the posterior 

 section. The base is at the same time more extended, the 

 sella-angle larger; and there is developed in the female a 

 striking tendency to prognathism as well as to doHchocephaly. 

 We may, therefore, say that the type of the female skull ap- 

 proaches, in many respects, that of the infant, and in a still 

 greater degree that of the lower races ; and with this is con- 

 nected the remarkable circumstance, that the difference be- 

 tween the sexes, as regards the cranial cavity, increases with 

 the development of the race, so that the male European excels 

 much more the female than the Negro the Negress. Welcker 

 confirms this statement of Huschke from his measurements 

 of Negro and German skulls ; more observations are, how- 

 ever, requisite before it can be accepted as generally true. 



