xxv] 



PRIMATES 



709 



and, except in Man, can be separated from them so as to be used 

 for grasping. In most but not in all Monkeys the thumb can be 

 used similarly, so that Monkeys are said to have four hands. There 

 are two large mammae or nipples situated on the breast. Other 

 mammae when present are vestigial and situated behind the func- 

 tional ones. 



There are two great divisions of the Primates, the LEMUROIDEA 

 and the ANTHROPOIDEA. The first of these includes some curious 

 little animals, of which the majority are found in the Island of 

 Madagascar, the rest in Africa, India and the Malay Archipelago. 

 Many of the species are nocturnal, move silently and have large 

 eyes, whence the name Lemur (Lat. lemu/res, goblins, spectres). 

 These animals have heads recalling those of rats, with no suggestion 



Fm. 358. Half front view of the skulls, A. of an old, B. of a young Gorilla, 



Gorilla savagei x . 



1. Parietal. 2. Sagittal crest. 3. Frontal. 4. Supra-orbital ridge. 

 5. Squamosal. 6. Maxilla. 7. External auditory meatus. 



of the human face, and in their brains and some other points they 

 are far below the Monkeys. The cerebral hemispheres do not cover 

 the cerebellum; the placenta of the embryo is spread evenly all 

 over the surface of the egg, and there are occasionally additional 

 mammae on the abdomen. Their incisor teeth are separated in the 

 middle line, but, as in all Primates, there are never more than two 

 on each side. The Ring-tailed Lemur, Lemur catta (Fig. 359), is 

 said to be an exception to the rule that the group is arboreal and 

 to live amongst rocks and bushes, but other authorities say that it 

 lives in troops amongst the forests of Madagascar. It is a gentle, 

 graceful creature with a plaintive cry. 



