THE DESCENT OR OBIGIN OF MAN 39 



long silky hairs; and such cases probably come under the 

 same head. 



It appears as if the posterior molar or wisdom teeth were 

 tending to become rudimentary in the more civilized races of 

 man. These teeth are rather smaller than the other molars, 

 as is likewise the case with the corresponding teeth in the 

 chimpanzee and orang ; and they , have only two separate 

 fangs. They do not cut through the gums till about the 

 seventeenth year, and I have been assured that they are 

 much more liable to decay, and are earlier lost, than the 

 other teeth; but this is denied by some eminent dentists. 

 They are also much more liable to vary, both in struc- 

 ture and in the period of their development, than the other 

 teeth." In the Melanian races, on the other hand, the 

 wisdom-teeth are usually furnished with three separate 

 fangs, and are generally sound; they also differ from the 

 other molars in size, less than in the Caucasian races.** 

 Prof. Schaaffhausen accounts for this difference between 

 the races by "the posterior dental portion of the jaw being 

 always shortened" in those that are civilized," and this 

 shortening may, I presume, be attributed to civilized men 

 habitually feeding on soft, cooked food, and thus using their 

 jaws less. I am informed by Mr. Brace that it is becoming 

 quite a common practice in the United States to remove 

 some of the molar teeth of children, as the jaw does not 

 grow large enough for the perfect development of the nor- 

 mal number." 



"With respect to the alimentary canal, I have met with 

 an account of only a single rudiment, namely, the vermi- 

 form appendage of the caecum. The c^cum is a branch or 



■*' Dr. Webb, "Teeth in Man andthe Anthropoid Apes," as quoted by Dr. 

 C. Carter Blake in "Anthropological Review," July, 1861, p. 299. 



« Owen, "Anatomy of "Vertebrates," vol. iii. pp. 320, 321, 325. 



** "On the Primitive Form of the Skull." Bng. translat. in "Anthropologi- 

 cal Review," Oct., 1868, p. 426. 



* Prof. Mantegazza writes to me from Florence, that he has lately beai 

 studying the last molar teeth in the different races of man, and has come to the 

 same conclusion as that given in my text, viz., that in the h^her or civilized 

 races they are on the road toward atrophy or elimination. 



