Chap. II. MENTAL POWEKS. 51 



as to nearly all the less cunning or weak-minded rats 

 having been successively destroyed by him. To main- 

 tain, independently of any direct evidence, that no 

 animal during the course of ages has progressed in 

 intellect or other mental faculties, is to beg the question 

 of the evolution of species. Hereafter we shall see that, 

 according to Lartet, existing mammals belonging to 

 several orders have larger brains than their ancient 

 tertiary prototypes. 



It lias often been said that no animal uses any tool ; 

 but the chimpanzee in a state of nature cracks a native 

 fruit, somewhat like a walnut, with a stone. 23 Bengger 24 

 easily taught an American monkey thus to break open 

 hard palm-nuts, and afterwards of its own accord it 

 used stones to open other kinds of nuts, as well as 

 boxes. It thus also removed the soft rind of fruit that 

 had a disagreeable flavour. Another monkey was taught 

 to open the lid of a large box with a stick, and after- 

 wards it used the stick as a lever to move heavv bodies ; 

 and I have myself seen a young orang put a stick into 

 a crevice, slip his hand to the other end, and use it in 

 the proper manner as a lever. In the cases just men- 

 tioned stones and sticks were employed as implements ; 

 but they are likewise used as weapons. Brehm 25 states, 

 on the authority of the well-known traveller Schimper, 

 that in Abyssinia when the baboons belonging to one 

 species (C. gelada) descend in troops from the moun- 

 tains to plunder the fields, they sometimes encounter 

 troops of another species (C. hamadryas), and then a 

 fight ensues. The Geladas roll down great stones, which 

 the Hamadryas try to avoid, and then both species, 



23 Savage and Wyman in 'Boston Journal of Nat. Hist.' vol. iv. 

 ]f43-44, p. 383. 



24 ' Siiugethiere von Paraguay,' 1830, s. 51-56. 



25 ' Thierleben,' B. i. s. 79, 82. 



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