THE DESCENT OR ORIGIN OF MAN 227 



formed by Mr. Denny that the most different kinds of dogs, 

 fowls, and pigeons, in England, are infested by the same 

 species of Pediculi or lice. Now Mr. A. Murray has care- 

 fully examined the Pediculi collected in different countries 

 from the different races of man;' and he finds that they 

 differ not only in color, but in the structure of their claws 

 and limbs. In every case in which many specimens were 

 obtained the differences were constant. The surgeon of a 

 ■whaling ship in the Pacific assured me that when the Pedi- 

 culi with which some Sandwich Islanders on board swarmed, 

 strayed on to the bodies of the English sailors, they died 

 in the course of three or four days. These Pediculi were 

 darker colored, and appeared different from those proper to 

 the natives of Chiloe, in South America, of which he gave 

 me specimens. These, again, appeared larger and much 

 softer than European lice. Mr. Murray procured four kinds 

 from Africa, namely, from the Negroes of the Eastern and 

 Western coasts, from 4;he Hottentots and Kaifirs; two kinds 

 from the natives of Australia; two from North and two from 

 South America. In these latter cases it may be presumed 

 that the Pediculi came from natives inhabiting different dis- 

 tricts. With insects slight structural differences, if constant, 

 are generally esteemed of specific value ; and the fact of the 

 races of man being infested by parasites which appear to be 

 specifically distinct might fairly be urged as an argument 

 that the races themselves ought to be classed as distinct 

 species. 



Our supposed naturalist, having proceeded thus far in 

 his investigation, would next inquire whether the races of 

 men, when crossed, were in any degree sterile. He might 

 consult the work' of Prof. Broca, a cautious and philosophi- 



(eal observer, and iu this he would find good evidence that 

 some races were quite fertile together, but evidence of an 

 opposite nature in regard to other races. Thus it has been 



8 "Transact. B. Soc. of Edinburgh," voL xxii., 1861, p. 561. 

 » "On the Phenomena of Hybridity in the Geaus Homo," Eng. translat., 

 1864. 



