CH. IV] MESITES AND LEPTOSOMA. 189 



The birds are not so strikingly peculiar as are the 

 mammals ; still there are not a few genera and species which 

 are restricted to Madagascar. Among these is the re- 

 markable Mesites, which is believed to be allied to the 

 Sunbittern of tropical America and to the Kagu of New 

 Caledonia, and is possibly to be regarded as a relic of a 

 primitive group of rail-like birds once dominant in all 

 parts of the world. Leptosoma is also a peculiar bird, 

 whose affinities are far from clear. The late Mr W. 

 A. Forbes 1 thought from his investigations into its 

 structure that it might be regarded as the type of a 

 distinct family near to the Rollers (Coraciidse). The 

 Cuckoo genus Coua is also peculiar to the island, as are 

 also the Vasa parrot; Coracopsis, and a few more types. On 

 the whole the avian fauna is not so remarkable as the 

 mammalian ; but in both cases the fauna of Madagascar 

 stands out as noteworthy by the absence of animals which 

 might be expected to occur just as much as by reason of 

 the peculiar types which do occur. There is an entire 

 absence of the characteristic African Elephants, Rhino- 

 ceroses, Anthropoid Apes, Lions, Hyaenas, &c. and among 

 birds, of Hornbills, Pla#taineaters, and Colies. 



The reptiles are almost as peculiar as the mammals. 

 The chief feature of the island is the presence of the 

 American genera Philodryas and Heterodon among snakes, 

 a fact which is remarkably paralleled by the Centetidse 

 among the Insectivora. There is an exactly analogous 

 case among lizards ; for two genera, Hoplurus, Chalarodon, 



i P. Z. S. 1880. 



