Dr. A. Gunther on the Geographical Distribution of Reptiles, 225 



a guide, Mr. Sclater states the following primary divisions of the 

 earth's surface ; — 



I. Palcearctic Region (Regio False arctica). 



Extent, — Africa, north of the Atlas ; Europe ; Asia Minor ; 

 Persia and Asia generally, north of the Himalaya Range ; upper part 

 of the Himalaya Range (?); Northern China, Japan, and the Aleutian 

 Islands. Approximate area of 14,000,000 square miles. 



II. Ethiopian or Western Palceotropical Region (Regio 

 iEthiopica). 



Extent. — xlfrica, south of the Atlas Range ; Madagascar ; Bour- 

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

 Gulf, south of 30° N. lat. Approximate area of 12,000,000 square 

 miles. 



III. Indian or Middle Palceotropical Region (Regio Indica). 



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

 lon; Burmah, Malacca, and Southern China ; Philippines ; Borneo ; 

 Java ; Sumatra and adjacent islands. An area of perhaps 4,000,000 

 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 (),500,000 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 is the con- 

 formity which this most natural division and the definition of the 

 limits of the regions exhibit in Herpetology. 



I. Palcearctic Region (Regio Paleearctica) . 



Characteristic forms. — {Calamarial) coronella, {Tachymenisl) 

 imiax, (Simotes'!) diadema, Rhinechis, Zamenis, Chorisodon, Ccelo- 

 peltis, Eryx, Pelias, Vipera, Echis, Cerastes. 



Form common to India. — Trigonocephalus. 



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, 



Ann. ^ Mag. N. Hist, Ser. 3. Vol. iii. 15 



