Ml 

 II. .Ethiopian or Western PoUBOtropical Region ( Regio 



£thiopica). 



Extent. — Africa, south of the Atlas Range ; liadagasi sar ; Hour- 

 bonj Mauritius; Socotra, and probably Arabia up to the Persian 

 Golf, south of 30° N. hit. Approximate area of 12,000,000 square 

 miles. 



III. Indian or Middle Palceotropical Ret/ion (Regio Imlica). 



Extent. — India and Asia generally, south of the Himalayas ; Cey- 

 lon; liurmah, Malaeca, and Southern China ; Philippines; Borneo . 

 Java; Sumatra, and adjacent islands. An area of perhaps 1,000,000 

 square miles. 



IV. Australian or Eastern Palceotropical Region (Regio 



Australiana). 



Extent. — Papua and adjacent islands ; Australia; Tasmania and 

 Pacific Islands. An area of perhaps 3,000,000 square miles. 



V. Nearctic or North American Region (Regio Nearctica). 



Extent. — Greenland and North America, down to centre of 

 Mexico. Area of perhaps G,f)00,0L)0 square miles. 



VI. Neotropical or South American Region (Regio Neotropica). 



Extent. — West India Islands ; Southern Mexico ; Central Ame- 

 rica, and whole of South America ; Galapagos Islands ; Falkland 

 Islands. Estimated area of about 5,500,000 square miles. 



The notices devoted to each region will show how great the con- 

 formity is, which this most natural division and the definition of the 

 limits of the regions find in Herpetology. 



I. Palcearctic Region (Regio Palsearctica). 



Characteristic forms. — (Calamarial) coronella, {Tachymenis 1 .) 

 virax, (Si/notes?) diadema, Rhinechis, Zamenis, Chorisodon, Vuln- 

 pi-ltts, Eri/.r, Pi-lias, J'ipera, Echis, Cerastes. 



Form common with India. — Trigonocephalies. 



This region is at once distinguished by the small number of generic 

 forms and of species ; great variety of amphibian life is produced only 

 by the sun of the Tropics, and dependent upon a similar variety of 

 the vegetative world. Where the soil is covered with social plants, 

 either trees or grasses, there we find an equal uniformity in tin' lite 

 of Reptiles, which uniformity is still more manifest in temperate 

 zones. 



North of the 62 N. L. no Snake has hitherto been found; anil 



thus the tbrtv species which live within the boundaries of this region 

 are very unequally distributed o\er an area of I 1,000,000 square 

 miles. We have on the average a single species to each 350,000 



-ipiare miles. All species are of a small size, duskj colour, ami of 

 a timid disposition; far the greatest part belongs to the CotuMxm . 



