OEIGIN OF WHITE MOUNTAIN FAUNA 37 



arctic species occurring on the White Mountain plateau.* 

 Among the beetles, too, and other groups of invertebrates, 

 there are many arctic forms, showing clearly the intimate 

 relationship that exists between the faunas of the White 

 Mountains and Labrador.f 



Even among mammals we have some most interesting 

 boreal representatives, the White Mountain lemming- vole 

 (Synaptomys spihagnicola) being peculiar to this region. J In 

 alluding to the mammalian fauna of Labrador I specially 

 dealt with this genus, and expressed the belief in its arctic 

 origin and subsequent southward dispersal (p. 28). 



If merely a few arctic plants and insects inhabited this re- 

 markable plateau, the argument might be permissible that 

 they had been carried southward by wind currents from their 

 northern home at great intervals of time and had successfully 

 established themselves in this manner on the White Moun- 

 tains, because the latter proved to be uninhabitable by the 

 fauna and flora of the surrounding country. No one, however, 

 who has seriously studied this congregation of animals and 

 plants as a whole, can for a moment entertain such an idea. 

 We must therefore take for granted that a fauna and flora 

 similar to that now existing in Greenland, Labrador and on 

 the White Mountains once extended over a large portion of 

 Canada and at any rate the north-eastern United States. The 

 problem to be solved is, what were the circumstances which 

 led those animals and plants to extend their range so much 

 southwards ? The prevalent theories regarding these move- 

 ments have already been referred to. They are simple enough. 

 Similar ones have been current in Europe for many years 

 past. I shall quote Professor Adams again, as his views 

 seem to me to express those generally entertained on 

 this subject. After an allusion to the final northward retreat 

 of the ice which he supposed to have crept down from the 

 north " grinding to pieces everything beneath its awful 



* Scudder, S. H., " Distribution of Insects in New Hampshire," 

 pp. 331341. 



t Gardiner, F., " Coleoptera of the White Mountains." 

 \ Miller, G., " Mammals of New Hampshire Mountains." 

 Adams, Charles C., " Post-glacial Origin of the life of North- 

 Eastern United States," p. 309. 



