CHAP, XIX.] 



REPTILES. 



379 



and the Indian Peninsula; and Langaha (2 sp.), confined to 

 agascar. 



Family 13.— DIPSADID^. (11 Genera, 45 Species.) 



Madagascar. 



The Dipsadidae, or Nocturnal Tree Snakes, are distinguished 

 from the last family by their dark colours and nocturnal habits. 

 They are about equally abundant in the Oriental and Neotropical 

 regions, less so in the Ethiopian, while only a single species 

 extends to North Australia. The following are the best known 

 genera : — 



Dipsas, comprising all the Oriental species with one in Asia- 

 Minor, and a few from the Moluccas, New Guinea, North Aus- 

 tralia, West Africa, and Tropical America ; Thamnodyastes, 

 Tropidodipsas, and several others, from Tropical America; Dipsa- 

 doboa, from West Africa and Tropical America ; Leptodeira, from 

 Tropical and South Africa, South America, and Mexico ; and 

 Pythonodipsas, from Central Africa. 



Family 14.— SCYTALID^. (3 Genera, 10 Species.) 



General Distribution. 



Neotropical Nearctic Pal^earctic | Ethiopian Oriental Adstralian 



Sub-regions. Sub-regions. Sub-regions. Sub-regions. Sub-regions. Sub-regions. 



2.3 



It is doubtful how far the three genera which constitute this 

 family form a natural assemblage. We can therefore draw no 

 safe conclusions from the peculiarity of their distribution — 

 Scytale and Oxyrhopus being confined to Tropical America ; 

 while Hologerrhum inhabits the Philippine Islands. 



