CH. II] NEARCTIC REGION. 93 



represented by an abundant variety of species; but as 

 many of them are common to this and to the Oriental 

 region which borders upon it, it is a little difficult to 

 disentangle the faunas of the two. Some of the mag- 

 nificent pheasants of the East, the genera Lophophorus, 

 Pucrasia, Thaumalea, and Crossoptilon, are characteristic ; 

 but these have already been mentioned as among the 

 birds characteristic of the region as a whole. There are 

 also species of Geriornis and Phasianus. 



II. The Nearctic region. 



This region consists of the whole of North America, 

 together with a portion of Mexico, into which, according to 

 Mr Wallace's map of the region, it sends a narrow tongue 

 along the central mountain range. As Mr Wallace has 

 pointed out, the greatest width of the continent in the 

 more arctic parts of it and its narrowness where the 

 climate becomes more congenial is largely responsible for 

 the comparative poverty of the fauna. 



List of families peculiar to the Nearctic region. 



Saccomyidce (Pouched rats), Haploodontidce (Ro- 

 dentia). 



Chamceidce (Passerines). 



Genera peculiar to the region. 



Synotus, Autrozous (Bats). 

 Condylura, Scapanus, Scalops (Moles). 

 Latax, Taxidea (Carnivora). 

 Antilocapra, Ovibus, JSaplocerus (Bovidae). 



