1890.] GENERA OF THE FAMILY SORICID^. 51 



genera of the two subfamilies. Thus Sorex is represented among 

 the white-toothed Shrews by Myosorex, Blarlna by Anurosorex, 

 and Crossojjus by Chimarrogale and Nector/ale. It would seem as if, 

 after the red-toothed Shrews diverged from the white-toothed, deve- 

 lopment had proceeded on somewhat similar lines in the descendants 

 of both according to similarity of environment and modes of life. 



To M. Milne-Edwards's list I have added four genera, Soriculus ^ 

 Hotiosorex, Myosorex'-, and Chimarrogale"', and omitted one, Neo- 

 sorex ', from it. I had long suspected the validity of the last-named 

 genus, founded for the reception of Sorex navigator, Baird, and 

 examination of a well-preserved specimen of a Water-Shrew lately 

 described ' by me under the name of Sorex hydrodromus, convinced me 

 that these species" must be merged in Sorex, of which they cannot even 

 be considered as representing a subgenus. S. hydrodromus, although 

 evidently aquatic like Crossopus fodiens, the fringes of the manus 

 and pes being even better developed than in that species, agrees in 

 all other generic characters with those of the genus Sorex as defined 

 in the synopsis above ; but while agreeing with Sorex palustris from 

 the adjoining continent of America in external characters, it differs 

 from it in the proportions of its teeth, resembling in this respect 

 the section of which iS. vulgaris is typical, while S. palustris agrees 

 with those represented by S. vagans. No better proof could be 

 afforded of the uselessness of retaining Neosorex as a distinct genus 

 for the American species characterized by the possession of swimming- 

 fringes in the digits, while the tail is simple as in Sorex. These 

 species are in fact aquatic forms of the genus Sorex. 



As I have omitted Neosorex so I am compelled to oxmt Atophy rax, 

 although the distinguishing marks of that genus have been so well 

 and clearly described by its founder. Dr. Merriam, through whose 

 kindness I have been enabled to examine the type, A. bendirii ~. This 

 species is, as noted by its discoverer, an inhabitant of marshy land, 

 and appears to me to present many characters intermediate between 

 Sorex 2^cthtstris and the terrestrial species of the genus, differing 

 from the former in the absence of well-defined fringes to the digits, 

 but agreeing with it closely in dentition, in the large size of the infra- 

 orbital foramen, and in the remarkable sliortness of the angular 

 process of the mandible. In fact there are no leading characters 

 which would enable me to define the genus, were I inclined to admit 

 it in my synopsis. 



* See tbe vpriter's paper " On the Genus Mi/osore.v," in P. Z. S. 1887, p. 575. 

 ^ Blyth, Journ. Asiiit. See. Beng. 18.55, xxiv. p. 3(j. 



3 This genus was defined by Anderson (Ann. & Mag. Nat. Hist. vol. xvi. 

 1875, p. 252), subsequently to the appearance of A. Milne-Edwards's synopsis. 



* Neosorex, Baird, Manuuals of North America (Reports of Explorations and 

 Surveys for a Route from the Mississippi to the Pacific Ocean, vol. vii. 1857). 



^ Annals & Mag. Nat. Hist., Nov. 1S«9, p. 374. 



6 From comparison of the types of 8orcx palustris and S. naviijator I am 

 much inclined to doubt the distinctness of the latter species. 

 '' Trans. Linnean Society of New York, vol. ii. 1884, pp. 217-225. 



