136 ZOOLOGICAL GEuGRAPHY. [paht hi. 



celebrated fur its power of ejecting a terribly offensive li(jiiid, the 

 odour of which is almost intolerable. The skunks are nocturnal 

 animals, and are generally marked, as in the species represented, 

 with conspicuous bands and patches of white. This enables 

 them to be easily seen at night, and thus serves to warn larger 

 animals not to attack them. To the left is the curious little 

 jumping mouse {Jaeulus kudsonnts), the American representative 

 of the Palcearctic jerboa. Climbing up a tree on the left is the 

 tree porcupine {Eretliizon dorsatus), belonging to the family Cer- 

 colabidse, wdiich represents, on the American continent, the por- 

 cupines of the Old World. In the background is the elk or 

 moose (AIccs amer^icamis), perhaps identical with the European 

 elk, and the most striking inhabitant of the northern forests of 

 America, as the bison is of the prairies. 



Birds. — Altliough the Canadian sub-region possesses very few 

 resident birds, the numbers which breed in it are perhaps greater 

 than in the other sub-regions, because a large number of circum- 

 polar species are foimd here exclusively. From a comparison of 

 ]Mr. Allen's tables it appears, that more than 200 species are 

 regular migrants to Canada in the breeding season, and nearly 

 half of these are la'nd-birds. Among them are to be found a 

 considerable number of genera of the American families Tyran- 

 . uidse and Mniotiltidas, as well as the American genera Sialia, 

 Progiu, Vireo, Cistothorus, Junco, Pipilo, Zonotrichia, Spizdla, 

 Melospiza, Molothrus, Agclccns, Cyanura, Sphyrapicus, and many 

 others ; so that the ornithology of these northern regions is still 

 mainly Nearctic in character. Besides these, it has such specially 

 northern forms as Surnia (Strigidse) ; Picoides (Picidse) ; Pinicola 

 (Fringillidce) ; as well as Leucosticte, Plecirophancs, Perisoreus, 

 and Lagopus, which extend further south, especially in the middle 

 sub-region. No less than 212 species of birds have been col- 

 lected in the new United States territory of Alaska (formerly 

 Russian America), Avhere a humming-bird (Selasphorus r2(fns) 

 breeds. The great majority of tliese are typically American, 

 including such forms as Colaptes, Helmintho'phaija, Siuriis, Den- 

 drceca, Myiodioctes, Passercuhts, ZonotricMa, Junco, Spizella, 

 Melospizpn^ Pas-'ierella, ScoleopJiagas, PefUocdes, and Bonasa ; 



