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PHYLUM CHORDATA : CLASS MAMMALIA 



Sumatra, Borneo, etc. ; the wild cat {F. catus) ; the Caffre 

 cat {F. caffra) of Africa and S. Asia, venerated and mum- 

 mified by the Egyptians, perhaps ancestral to the domestic 

 cat. 

 A high degree of specialisation for carnivorous habit is well 

 illustrated by the sabre-toothed tigers {MacHcBrodus) of 

 Tertiary ages, whose serrated upper canines were sometimes 

 7 in. long. 

 Family Viverridae — Old World forms, such as civets {Viverra), of 

 Africa and India ; genets [Genetta), of S. Europe, Africa, and 

 S.-W. Asia ; ichneumons or mongooses {Herpestes), in Spain, 

 Africa, India, Indo-Malaya. 

 Family Proteleidae — represented by Proteles cristatus, the hyaena- 

 like aard-wolf of S. Africa. 

 Family Hyeenidse — represented by the genus Hycena, found in 

 Africa and S. Asia. The tympanic bulla is not divided by a 

 septum. 



(2) Cynoidea — Dog-like Carnivores 



Family Canidse — including forms intermediate between the cats and 

 the bears. The dentition is more generalised than in the 



Fehdae, its usual formula is ^^. Within the tympanic bulla 



3143 ^ ^ 



there is only a rudimentary septum. The paroccipital process 



in contact with the bulla is prominent. The c^cum is either 



short and simple or long and pecuharly folded upon itself. 



Examples. — The genus Canis has representatives in all parts 



of the world — the wolves (C. lupus, etc.), the jackals 



(C. aureus, mesomelas, etc.), the domestic dogs (C. faniili- 



aris), the foxes (C. vulpes, etc.), the Cape hunting dog 



(Lycaon), the bush-dog (Icticyon) of Guiana and Brazil, and 



the primitive Otocyon megaloHs from S. Africa. In the dog 



the dental formula is ^-^ ; the upper carnassial or fourth 



3143 

 premolar has a stout bilobed blade, the lower carnassial or 



first molar has a compressed bilobed blade. The skull is 



more elongated than in the cats ; the orbits are very widely 



open posteriorly ; the clavicles are very small ; the limbs 



are digitigrade ; there are five toes on the fore-feet, but the 



short thumb does not reach the ground ; there are only four 



toes on the hind-feet, but in domestic dogs the rudiment of 



the hallux is sometimes enlarged as the " dew-claw " ; the 



claws are non-retractile and blunt. 



(3) Arctoidea — Bear-like Carnivores 



The tympanic bulla shows no trace of an internal septum ; the 

 paroccipital process of the exoccipital is quite apart from the 

 bulla, and widely separated from the mastoid process of 

 the periotic. The limbs are plantigrade or sub-plantigrade, 

 and always bear five toes. There is no caecum. 



