48 THE DESCENT OF MAN 



All wlio have liad charge of menageries admit this fact, and 

 we see it plainly in our dogs and other domestic animals. 

 Brehm especially insists that each individual monkey of 

 those which he kept tame in Africa had his own peculiar 

 disposition and temper: he mentions one haboon remarkable 

 for its high intelligence; and the keepers in the Zoological 

 Gardens pointed out to me a monkey, belonging to the Wew 

 World division, equally remarkable for intelligence. Eeng- 

 ger, also, insists on the diversity in the various mental char- 

 acters of the monkeys of the same species which he kept in 

 Paraguay ; and this diversity, as he adds, is partly innate, 

 and partly the result of the manner in which they have been 

 treated or educated.* 



/» I have elsewhere" so fully discussed the subject of Inheri- 

 tance, that I need here add hardly anything. A greater 

 number of facts have been collected with respect to the 

 transmission of the most trifling, as well as of the most 

 important, characters in man than in any of the lower ani- 

 mals ; though the facts are copious enough with respect to 

 the latter. So in regard to mental qualities, their transmis- 

 sion is manifest in our dogs, horses, and other domestic ani- 

 mals. Besides special tastes and habits, general intelligence, 

 courage, bad and good temper, etc. , are certainly transmitted. 

 With man we see similar facts in almost every family; and 

 we now know, through the admirable labors of Mr. Gralton, " 

 that genius, which implies a wonderfully complex combina- 

 tion of high faculties, tends to be inherited; and on the 

 other hand, it is too certain that insanity and deteriorated 

 mental powers likewise run in families. X 



With respect to the causes of variability, we are in all 

 cases very ignorant; but we can see that in man, as in the 

 lower animals, they stand in some relation to the conditions 

 to which each species has been exposed during several gen- 



8 Brehm, "Thierleten," B. 1. s. 58, 81. Eengger, "Saugethiere von Para- 

 guay," 8. 57. 



» "Variation of Animals and Plants under Domestication," vol. ii. chap. xiL 

 '» "Hereditary Genius: an Inquiry into its Laws and Consequences," 1869. 



