274 ZOOLOGICAL GEOGRAPHY. [part hi 



sented by a single group in Africa, with two peculiar forms on 

 the West coast. They also re-appear under peculiar and isolated 

 forms in Southern India and Malaya, and are evidently but the 

 remains of a once wide-spread group, since in Eocene times they 

 inhabited North America and Europe, and very probably the 

 whole northern hemisphere. The Insectivora are another group 

 of high antiquity, widely scattered over the globe under a 

 number of peculiar forms ; but in no equally limited area repre- 

 sented by so many peculiar types as in Madagascar. South and 

 West Africa are also rich in this order. 



The Carnivora of Madagascar are mostly peculiar forms of 

 Viverridas, or civets, a family now almost confined to the 

 Ethiopian and Oriental regions, but which was abundant in 

 Europe during the Miocene period. 



The Potamochcerus is a peculiar species only, which may be 

 perhaps explained by the unusual swimming powers of swine, 

 and the semi-aquatic habits of this genus, leading to an immi- 

 gration at a later period than in the case of the other Mammalia. 

 The same remark will apply to the small Hippopotamus, which 

 was coeval with the great Struthious bird iEpiornis. 



Rodents are only represented by three peculiar forms of 

 Muridse, but it is probable that others remain to be discovered. 



Birds. — Madagascar is exceedingly rich in birds, and espe- 

 cially in remarkable forms of Passeres. No less than 88 genera 

 and 111 species of land-birds have been discovered, and every 

 year some additions are being made to the list. The African 

 families of Passeres are almost all represented, only two being- 

 absent — Parid* and Fringillidse, both very poorly represented in 

 Africa itself. Among the Picarhe, however, the case is very 

 different, no less than 7 families being absent, viz. — Picidse, 

 or woodpeckers ; Indieatoridre, or honey -guides ; Megaleemidae, 

 or barbets ; Musophagidse, or plantain-eaters ; Coliidse, or colies; 

 Bucerotidse, or hornbills ; and Irrisorida?, or mockers. Three of 

 these are peculiar to Africa, and all are well represented there, 

 so that their absence from Madagascar is a very remarkable fact. 

 The number of peculiar genera in Madagascar constitutes one of 

 the main features of its ornithology, and many of these are so 



