192 LLOYDS NATURAL HISTOPvY. 



the Orang. Its presence, however, while acting somewhat less 

 favourably in regard to the climbing capacities of these animals, 

 whose habits are less essentially arboreal than the Orangs', 

 beneficially assists them in walking, affording them a firmer 

 support on the ground. In the Chimpanzee there is always a 

 semi-lunar fold {plica semiliina7ds) in the inner corner of the 

 eye, corresponding to the nictitating membrane (or third eye- 

 lid) of birds. In some of the Lemuroids it is well developed 

 {siipra^ vol. i., p. 90), and is large in some races of men^ 



The Chimpanzee is confined to the West African Sub-region, 

 as defined by Dr. Bowdler Sharpe. It is known from Loango, 

 along the banks of the Upper Congo, and Mr. Monteiro 

 (P. Z. S., 187 1, p. 544) says it is quite unknown to the south of 

 the Congo ; it also occurs throughout the country of the Man- 

 yema, in Central Africa, where Livingstone describes it under the 

 name of Soko; and southward as far as 10° south latitude, to 

 Lake Moero. Schweinfurth has recorded it from the Niam- 

 niam country. 



The Chimpanzees inhabit forest regions, and feed on wild 

 fruits in the woods, and the products of cultivated gardens, 

 not rejecting, when they can capture it, animal food. They 

 live in separate famiUes, or in hmited communities of small 

 families mixed together, but each male lives with his own 

 single female. They are more arboreal than the Gorilla, but 

 much less so than the Orangs. In many districts they seem 

 to live on the ground. 



They emit loud cries, shrieks, and howls in the morning and 

 evening, and often during the night. " Since they are really 

 accomplished in the art of bringing forth these unpleasant 

 sounds, which may be heard at a great distance, and are re- 

 produced by the echoes, it is impossible to estimate the number 



