THE BABOONS. 27 I 



members of the genus. In regard to the bright coloration of 

 the callosities and posterior parts of this and other Baboons, 

 Mr. Darwin remarks : " In the discussion on sexual selection in 

 my ' Descent of Man,' no case interested and perplexed me so 

 much as the highly-coloured hinder ends and adjoining parts 

 of certain Monkeys. As these parts are more brightly coloured 

 in one sex than the other, and as they become more brilliant 

 daring the season of love, I concluded that the colours had 

 been gained as a sexual attraction. ... I had, however, 

 at that time no evidence of Monkeys exhibiting this part of 

 their bodies during their courtship. ... I have lately 

 read [in an article by J. von Fischer, of Gotha, pubHshed in 

 April, 1876] an account of the behaviour of a young male 

 Mandrill when he first beheld himself in a looking-glass, and it 

 is added, that after a time he turned round and presented his 

 red hinder end to the glass. Accordingly I wrote to Herr J. von 

 Fischer to ask what he supposed was the meaning of this 

 strange action. He says that he was himself at first perplexed 

 . . . and was thus led carefully to observe several indi- 

 viduals of various other species of Monkeys, which he has long 

 kept in his house. He finds that not only the Mandrill (C 

 mormon) but the Drill (C leiicophceiis) and three other kinds of 

 'Edihoons {C. hafnadryas,C. sphinx, 2indC.balmtn) . . . turn 

 this part of their bodies, which in all these species is more or 

 less brightly coloured, to him when they are pleased, and to 

 other persons as a sort of greeting. . . . From these facts 

 von Fischer concludes that the Monkeys which behaved in 

 this manner before a looking-glass . . . acted as if their 

 reflection were a new acquaintance. ... It deserves 

 especial attention that von Fischer has never seen any species 

 purposely exhibit the hinder part of its body, if not at all 



