534 Vertebrata. 



No perforation in the septum between the orbit and the temporal 

 fossa. Caecum small. Cheek-pouches frequently^ ischial callosities 

 usually present; tail never developed into an organ of prehension, 

 often absent. Occur exclusively in the Old World. 



1. Cynomorphx. Below each of the thick, broad ischia, there is a naked 

 coloured portion of the skin, an ischial callosity. NaUs relatively much 

 arched. Tail usually present. Hind somewhat longer than fore limbs. Cheek 

 pouches iisually present. External incisor of the lower jaw narrower than (or 

 the same breadth as) the inner ; first molar of the lower jaw with four tubercles. 

 The thorax compressed (as is usual in the Mammalia) ; the manubrium of the 

 sternum broad, the rest very narrow. Pelvis long and naiTOw ; the symphysis 

 (the line of junction of the two halves) long, the ilia long and naiTOw. The 

 sacrum consists of t h r e e vertebrae. 



(a) Cercopithecidss. Tail long ; muzzle short ; cheek pouches present ; 

 several African species. Closely alhed is the Magotor Barbary Macaque 

 {Inuus ecaudatus) ; with mdimentary knob-like tail ; occurring in North Africa 

 and Gibraltar (the only European Ape). The Baboons (Cynocephalus), dis- 

 tinguished from the Cercopithecidae by the very long, canine muzzle ; taU long or 

 short; cheek pouches present. They usually remain on the ground, are only 

 occasionally seen in trees. Africa and Arabia. 



(6) Semnopitheci<J8e, characterised by the absence of cheek pouches ; and 

 the division of the stomach into several sections (whilst in other Apes 

 it is simple). Amongst foi-ms belonging here is S. nasicus, of Borneo, 

 with very long nose. Colobus, in which the poUex is wanting, is nearly allied ; 

 Africa. 



2. Anthropoid Apes {Anthropomorphse). Ischial callosities 

 absent or small. Nails arched in the Gibbons, more flattened in other forms. 

 Gibbons well clothed with hair ; in the others, certain regions sparsely covered. 

 Tail absent (rudimentary caudal region of the vertebral column consisting of 

 four or five small vertebrse) ; fore limbs longer than hind ; no cheek 

 pouches; outer lower incisor broader than the inner, fii'st molar of the lower 

 jaw with five tubercles ; thorax broader than in the Cynomorphse ; pelvis in 

 the Gibbons Uke that of the Cynomorphse ; in othei-s, the iha are broader, the 

 symphysis is short ; the sacrum consists of five vertebrae.* The Anthropoid 

 Apes are more exclusively arboreal than are the other Oatan-hinaa ; they do not 

 walk like ordinai-y Mammalia (as the Platyrrhinae do), but upon their hind legs, 

 supporting themselves by the knuckles of the fore limbs, or they move in other 

 aberrant ways. The largest Monkeys belong here. 



(a) Gibbons (Hylobates) corae nearest to the Oynomoi-phae; they possess 

 small ischial callosities ; the naUs are strongly arched ; and the pelvis is long and 

 narrow, Uke that of the Cynomoi-phae ; they are covered with thick hair, and 

 have extraordinarily long arms, which they swing as they walk on their hind 

 hmbs. Smaller than those following : sevei-al species in Asia. 



(6) Orang-Utang {Pithecus saiyrus). Head almost conicaUy arched 

 above, face very projecting, nose flattened ; fore hmbs very long, reaching to the 

 ankles when the animal stands upright ; hand and foot long and narrow ; hallux 

 fairly small; reddish brown; height up to 1'5 m. (measured in the upright 

 position) : Sumatra and Borneo. 



* In the Orang, the Chimpanzee, and the Gorilla (and in one of the Gibbons 

 Hylobates syndactylus), just below the skin, there are one or two large air sacs; 

 they proceed from the larynx, and extend on to the neck and thorax ; they may be 

 inflated with air and enormously expanded. 



