THE ANTHKOPOMOKPHA. 403 



per part of the shaft is not bent as in the Gynomorpha. The 

 radius is capable of complete pronation and supination. 



The relative proportions of the incisor teeth are the same 

 as in Man ; that is to say, the inner upper incisors and tlie 

 outer lower incisors are larger than the others. The crowns 

 of the upper and lower molars have the same patterns as those 

 of iMan. 



The caudal muscles are small or absent. When the pollex 

 has a flexor tendon, that tendon is not a slip given off from 

 one common to the flexor pollicis and flexor perforans, as in 

 the Gynomorpha. The plantaris does not pass over a pulley 

 furnished by the calcaneal process, as in the Gynomorpha ; 

 and the flexor brevis has an origin from that process. The 

 peronoBUS quinti digiti has not been observed. 



There are three well-marked genera of Anthropomorpha — ■ 

 ITylobates, Pithecus, and Troglodytes ; and perhaps a fourth, 

 Gorilla, may be advantageously separated from the last- 

 named. 



Pithecus, the Orang, has the smallest distributional area, 

 being confined to the islands of Borneo and Sumatra ; Hylo- 

 hates, the Gibbons, of which there are several species, is found 

 over a considerable area of Eastern Asia and the islands of the 

 Malay Archipelago. The Ghimpanzee and Gorilla are met 

 with only in the intertropical parts of West Africa. 



The Gibbons are those Anthropomorpha which are most 

 nearly allied to the Gynomorpha. They possess ischial cal- 

 losities, and the nails of the pollux and hallux, only, are broad 

 and flat. The arms are so long that the points of the fingers 

 readily touch the ground when the animal stands upright, as 

 it very readily and commonly does. The Gibbons also run 

 with great swiftness, putting the sole of the foot flat on the 

 ground and balancing themselves with their long arras. Nev- 

 ertheless, they are essentially arboreal animals, leaping from 

 bough to bough of the trees in the forests which they frequent 

 with marvellous force and precision. The manus is longer 

 than the pes, and the antibrachium considerably longer than 

 the brachium. The Gibbons do not exceed three feet in 

 heio"ht; their heads are small, and their bodies and limbs 

 remarkably slender. 



None of the other Anthropomorpha have callosities, and 

 the nails of all the digits are flattened. They are all heavier 

 in make, with proportionally shorter limbs and larger heads 

 than the Gibbons. In the Orangs, which rarely attain a stat- 

 ure of more than four feet and a half, the arms are very long, 



