﻿Dec, 1895.] 



SOREX PALUSTRIS, 



45 



Subgenus NEOSOREX Baird. 



Neosorex Baird, Mamm. N. Am., p. 11, 1857. Type, Neosorex navigator Baird. 



Inner side of canine and incisors without secondary cusps ; fourth 

 upper incisor well developed; brain case broad (ratio of cranial breadth 

 to total length of skull ranging- from 52 to 56); mandible slender and 

 Jightly built; feet conspicuously fringed with bristle like hairs, as in 

 Crossopns. 



The subgenus Neosorex was first described in 1857 by Baird, who 

 considered the single species known to him entitled to full generic 

 rank. In this decision he was followed by authors until 1890, when 

 Dr. Dobson (Proc. Zoo) iSoc, London, p. 51) came to the conclusion 

 that iV'eosorea? "can not even be considered as * * * a subgenus " 

 Dr. Merriam has more recently (North American Fauna, No. 5, July, 

 1891, p. .35) expressed the opinion that Neosorex is "a very good sub- 

 genus," and this ruhng appears to be the most satisfactory. 



Neosorex is confined to America, and although not closely related to 

 the Old World Crossopus^ shows a remarkable parallelism with the latter 

 both in habits and m external appearance. Both are aquatic, inhab- 

 iting marshes and the borders of streams, and the likeness between 

 freshly kdled specimens of the two Shrews is very remarkable. Crosso- 

 pus IS, however, the more robust animal with shorter tail and broader 

 muzzle. 



SOREX PALUSTRIS Richardson. 



(PI V fig, 1 ; PL VI, figs. 1 and \a.) 



1828. /Soj-ex^^^^ws/ns Richardson, Zool. Jour., Ill, p. 517. (Hudson Bay to Rocky Mts.) 

 1853. Sorex palustris k\\({ and Bach., Quadrupeds N. Am., Ill, p. 108, PI. CXXV. 

 1890. Sorex imlustris Dobson. Mon, lusectivora, Part III, fasc. 1, PI. XXIII, fig. 18 

 (teeth of type). 



1894. Sorex palusiris Miller, Proc. Bost. Soc. Nat. Hist., XXVI, p. 183. (Minnesota.) 



Ty2)e localiiy. — Unknown; somewhere in the region between Hudson 

 Bay and the Rocky Mountains. (Type in the British Museum.) 



GeograpMc distrihnf ion. —Boreal zone from Hudson Bay and central 

 Minnesota west to the Eocky Mountains. 



General characters.— Sorex palnstris is distinguished by its subgeneric 

 characters from all other eastern American Shrews except 8. albiharhis. 

 From the latter it is separated by its shorter, broader, more heavily 

 pigmented uuicuspicl teeth, and the sharply defined whitish color of 

 the belly. 



(7o?or.— Dorsal surface very dark seal brown with a slight gloss, each 

 hair with a narrow subterminal band of smoke gray separating the 

 seal brown tip from the slate gray under fur, and producing a grizzled 

 appearance when the animal is viewed in certain lights; ventral sur- 

 face very pale smoke gray, nearly white, and often faintly tinged with 

 cream color; the color of the belly extending a short distance on the 



