Faunal Regions 



FAUNAL REGIONS 



That branch of zoological science which treats of the geograph- 

 ical distribution of animals is known as zoogeography. None of the 

 zoological sciences has contributed more to a knowledge of the facts 

 with which zoogeography deals than the science of entomology. 



Various divisions of the surface of the earth, based upon the 

 character of the living beings which inhabit them, have been sug- 

 gested. At the present time, however, it is agreed that in a 

 general way five major subdivisions are sufficient for the purposes 

 of the science, and we therefore recognize five faunal regions, 

 namely, the Palcearctic, which includes the temperate regions of 

 the eastern hemisphere; the Indo-Malayan, covering the tropics 

 of Asia and the islands lying south of that great continent, in- 

 cluding Australia ; the Ethiopian, covering the continent of Africa 

 south of the lands bordering on the Mediterranean, and extending 

 northward into the southern part of Arabia; the Neotropical, 

 covering the continent of South America and the islands of the 

 Caribbean Sea and the Gulf of Mexico; and, finally, the Nearctic, 

 covering the temperate and polar regions of North America. The 

 butterflies with which this volume deals are mostly nearctic 

 species, only a few species representing the neotropical region 

 being found as stragglers into the extreme southern portion of 

 the United States. 



These five faunal regions are characterized by the presence of 

 certain groups of insects which are more or less peculiar to them. 

 In the Palaearctic Region, for instance, we find a very great de- 

 velopment of the Satyrince, of the genera Argynnis, Melitcea, 

 and Lyccena, and of the genus Colias. The genus Papilio is but 

 poorly represented, there being only three species found on the 

 entire continent of Europe, and comparatively few in Asia north 

 of the Himalayan mountain-ranges. 



As soon as we pass from the boundaries of the Palaearctic 

 Region into India there is discovered a great number of species 

 of the genus Papilio. The Euploeince, of various genera, swarm, 

 and splendid creatures, magnificent in color, present themselves, 

 replacing among the Nymphalince the small and obscurely col- 

 ored forms which are found among the mountains of Europe and 

 on the great Asiatic steppes. In the Indo-Malayan Region one 



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