ZOO-GEOGRAPHICAL REGIONS. 805 



changes of the earth and its climate, and (6) the bionomic 

 relations. 



Zoo-geographical regions. I shall simply quote a para- 

 graph from Professor Heilprin's work, The Geographical 

 and Geological Distribution of Animals (Internat. Sci. 

 Series. London, 1887), a very valuable book for the 

 student, especially as it considers distribution in space 

 and time together. 



"By most naturalists (Wallace, Sclater, and others) the 

 terrestrial portion of the earth's surface is recognised as 

 consisting of six primary zoological regions, which corre- 

 spond in considerable part with the continental masses of 

 geographers. These six regions are 



" i. The Palcearctic, which comprises Europe, temperate 

 Asia (with Japan), and Africa north of the Atlas Moun- 

 tains ; also Iceland, and the numerous oceanic islands of 

 the North Atlantic ; 



" 2. The Ethiopian, embracing all of Africa south of the 

 Atlas Mountains, the southern portion of the Arabian Pen- 

 insula, Madagascar, and the Mascarene Islands, and which, 

 consequently, nearly coincides with the Africa of geo- 

 graphers ; 



" 3. The Orientals Indian, which embraces India south 

 of the Himalayas, Farther India, Southern China, Sumatra, 

 Java, Bali, Borneo, and the Philippines ; 



"4. The Australian, comprising the continent of Aus- 

 tralia, with Papua or New Guinea, Celebes, Lombok, and 

 the numerous islands of the Pacific ; 



"5. The Nearctic, which embraces Greenland, and the 

 greater portion of the continent of North America (excluding 

 Mexico) ; 



"6. The Neotropical, corresponding to the continent of 

 South America, with Central America, the West Indies, and 

 the greater portion of Mexico." 



Professor Heilprin makes several modifications on this 

 scheme of distribution : (a) uniting Palsearctic and Nearctic 

 in one Holarctic realm; (b) establishing a special Poly- 

 nesian realm for the scattered island groups of the Pacific ; 

 and (c) defining three transition regions (i) around the 

 Mediterranean, intermediate between Palsearctic, Ethiopian, 

 and Oriental, (2) Lower California between Western Hoi- 



