486 



RODENTIA 



Chcetomys. 1 — Distinguished by the shape of its skull and the 

 greater complexity of its teeth. It contains only one species 

 (C. snbsjrinosus), a native of the hottest parts of Brazil. 



Subfamily Hystrieinse. — Molars semi -rooted; clavicles incom- 

 plete ; soles smooth ; a rudimentary pollex ; six mammae ; tail not 

 prehensile. Now confined to the Old World, where they occur in 

 Southern Europe, Africa, India, and the Malay Archipelago as 

 far eastwards as Borneo. Habits terrestrial and nocturnal. Three 

 genera. 



Hystrix. 2 — This genus is readily characterised by the inflated 

 skull, in Avhich the nasal chamber is often considerably larger than 



Fig. '215. — The Common Porcupine (HystrLc cristata). 



the brain-case, and by the short tail, tipped Avith numerous slender 

 stalked open quills, Avhich make a loud rattling noise when the 

 animal moves. Vertebra? : C 7, D 1 5, L 4, S 4, C 1 2. The best- 

 known member is the Common Porcupine (II. cristata, Fig. 215), 

 which occurs throughout Southern Europe and North and West 

 Africa, but is replaced in South Africa by H. africce-australis, and 

 in India by the Hairy-nosed Porcupine (H. leucura). 



The following account of the habits of the last-named species 

 is from Dr. Jerdon : " Hystrix leucura is found over a great part of 

 India, from the lower ranges of the Himalayas to the extreme south, 

 but does not occur in lower Bengal, where it is replaced by H. 

 l» ngalensis. It forms extensive burrows, often in societies, in the 

 sides of hills, banks of rivers and nullas, and very often in the 



1 Gray, Proc. Zool. Soc. 1843, p. 21. 

 - Linn. Syst. Nat. 12th ed. vol. i. p. 76 (1766). 



