Natural History 485 



themselves except at the breeding season, as in the case of ele- 

 phants and stags. An experienced old female leads the hinds and 

 the young; a male in his prime leads the stags. Where the pair 

 do not live together throughout the year, and where the care of 

 the family devolves wholly on the mother, the terms monogamous 

 and promiscuous have not much meaning. There is pairing rather 

 than mating. A female mammal may pair with one male one year 

 and with another next year, or with several in one year. But our 

 knowledge of these matters is sadly lacking in precision. It has 

 to be remembered that in most cases the pairing time is sharply 

 punctuated and of short duration. 



It is interesting to inquire into family life among apes. The 

 Gibbons (Hylobates) of southeast Asia are the smallest of the 

 anthropoid apes, rarely over three feet high. But they have 

 disproportionately long arms, the hands touching the ground 

 when the animal stands erect. They are fond of swinging like 

 acrobats below the branches with their arms above their head. 

 They can swing clear for 12-18 feet with the greatest ease, and 

 pass from tree to tree unwearyingly. During the day they keep 

 to the tree-tops, especially on the mountain-sides ; towards evening 

 they come cautiously "waddling" down in the open ground search- 

 ing for fruit. Their voice is extraordinarily strong, especially in 

 the males, and not unmusical. They are sociable and talkative. 

 The Orang (Simla satyrus) of the forests of Borneo and Sumatra 

 stands about four feet high and is very strongly built. It is highly 

 intelligent, but somewhat sluggish in habit, climbing slowly, keep- 

 ing to the trees except at night, when it sometimes searches on the 

 ground for fallen fruit. It uses its arms as crutches or goes on 

 all-fours. It makes for resting purposes a sort of platform nest 

 of branches, but it moves on and makes another every second day 

 or so. The male orang lives apart; but the mother keeps her 

 family with her for some time. The Chimpanzee (Anthropo- 

 pithecus troglodytes) of African equatorial forests may be five 

 feet high, but it is not so bulky as the Orang, and it is as good a 



