chap, iv.] ZOOLOGICAL REGIONS. 61 



half of Ceylon. 4. The Lemurian region ; consisting of Mada- 

 gascar and its adjacent islands. 5. The Austral-Asian region ; 

 which is the Indian region of Mr. Sclater without the portion 

 taken to be added to the Ethiopian region. 6. The Melanesian 

 region ; which is the Australian region of Mr. Sclater without 

 New Zealand and the Pacific Islands, which form 7. the 

 Polynesian region. Mr. Blyth thinks this is " a true classifi- 

 cation of zoological regions as regards mammalia and birds." 



In an elaborate paper on the birds of Eastern North America, 

 their distribution and migrations (Bulletin of Museum of Com- 

 parative Zoology, Cambridge, Massachusetts, Vol. 2), Mr. J. A. 

 Allen proposes a division of the earth in accordance with what 

 he terms, " the law of circumpolar distribution of life in zones," 

 as follows : 1. Arctic realm. 2. North temperate realm. 3. 

 American tropical realm. 4. Indo-African tropical realm. 

 5. South American tropical realm. 6. African temperate realm. 

 7. Antarctic realm. 8. Australian realm. Some of these are 

 subdivided into regions; (2) consisting of the American and 

 the Europaeo- Asiatic regions ; (4) into the African and Indian 

 regions ; (8) into the tropical Australian region, and one com- 

 prising the southern part of Australia and New Zealand. The 

 other realms each form a single region. 



Discussion of proposed Regions. — Before proceeding to define 

 the regions adopted in this work, it may be as well to make 

 a few remarks on some of the preceding classifications, and 

 to give the reasons which seem to render it advisable to adopt 

 very few of the suggested improvements on Mr. Sclater's 

 original proposal. Mr. Blyth's scheme is one of the least 

 natural, and also the most inconvenient. There can be little 

 use in the knowledge that a group of animals is found in the 

 Boreal Eegion, if their habitat might still be either Patagonia, 

 the West Indies, or Japan ; and it is difficult to see on what 

 principle the Madagascar group of islands is made of equal 

 rank with this enormous region, seeing that its forms of life 

 have marked African affinities. Neither does it seem advisable 

 to adopt the Polynesian Eegion, or that comprising New Zealand 

 alone (as hinted at by Professor Huxley and since adopted by 



