MUSEUM OF COMPARATIVE ZOOLOGY. 405 



the artic fox (Vulpes lagopits), the musk ox (Ovibos moschatus), the 

 lemmings {Myodes), the small northern race of the caribou or reindeer, 

 the Eskimos, etc. 



The Hudsonian Fauna forms the southern limit of the polar hare 

 {Lepus glacialis) and the northern limit (at least in wiuter) of the 

 Lynx canadensis, Mustela " americana," Mustela Pennantii, Pulorius 

 vulgaris, Putorius ermineus, Ursus " americanus" Ursus " horribilis" 

 Sciurus hudsonius, Arctomys monax, Vespertilio subidatus, and others. 



The Canadian Fauna forms, at present,* the southern limit of Mustela 

 Pennatii, Mustela " americana" Gulo luscus, Arvicola xanthognathus, 

 Erethizon dorsatus, Alces malchis, Rangifer tarandus, etc., and the 

 northern limit of Felis concolor, Lynx rufus, Mephitis mephitica, Pro- 

 cyon lotor, Bos americanus, Condylura cristata, Blarina brevicauda, 

 and others. 



The Alleghanian Fauna forms the southern limit of Lynx cana- 

 densis, Sciurus hudsonius, Arvicola Gapperi, Jaculus hudsonius, Lepus 

 americanus, Cervus canadensis, Sorex platyrhinus, Condylura cristata, 

 and doubtless of several other species ; and the northern limit of Sciu- 

 rus cai'olincnsis, Lepus sylvaticus, Arvicola pinetorum, Cervus virgini- 

 anus, Scalops aquaticus, etc. 



The Carolinian Fauna forms the southern limit of Mustela vulgaris, 

 Tamias striatus, Arctomys monax, and Fiber zibethicus ; and the north- 

 ern limit of Vulpes virginianus, Nycticejus crepuscularis, Didelphys 

 virginiana, etc. 



The Louisianian Fauna seems to form the southern limit of Putorius 

 vison, Blarina brevicauda, Scalops aquaticus, and doubtless thus limits 

 several other species, though not a small proportion of those which 

 occur in this fauna range also into South Florida, or into the Floridian 

 Fauna. The Louisianian Fauna limits the northward range of Neo- 

 toma fioridana, Reithrodon humilis, Sigmodon hispidus Hesperomys 

 palustris, Geomys pineti, and Lepus palustris. 



In respect to reptiles, a similar proportion of species are limited in 

 either their northward or southward range b) r each fauna. Several 

 species of batrachians range into the Hudsonian Fauna, but apparently 

 this fauna must be the northern limit of their distribution. The Cana- 



* It is probable that some of the fur-bearing species, as well as Hystrix dorsatus, the 

 moose and the caribou, once ranged southward throughout the Alleghanian Fauna, and 

 have been exterminated there by man. 



