95 



jaw, directed nearly horizontally forward; the upper much curved, and 

 forming a hook ; the lower straighter, and with the cutting edges lobed. 

 They are an abundant and widely distributed family, remarkably vora- 

 cious, feeding on worms, insects, and moUusks, sometimes destroying 

 small vertebrates and readily devouring each other. They are chiefly 

 nocturnal ; some species of Neosorex are aquatic. The young, at birth, 

 are naked and blind. None hibernate, but all are about in the coldest 

 weather. 



The Shrews are represented in America by three genera; Sorex (L ), 

 the most generalized type, also occurring in the Old "World; Neosorex 

 (Bd.) includes the Water Shrews, and is peculiar to North America, 

 where it replaces Crossopus, of the Old World ; Blarina, the most charac- 

 teristic American genus, has no exact Old World analogue. 



All are small and difficult to study. Measurements of such small ani- 

 mals are often fallacious. Color variation , due to age, sex, season, or 

 geographical distribution, hav'e furnished data for worthless species ; 

 moreover, the tail and lips, and possibly the feet, undergo extraordinary 

 changes at the rutting season, so that such terms as " pachyurus," " longi- 

 rostris," ^' platyrhymis" are of doubtful implication. Perhaps no family 

 of North American mammals, of equal abundance, is so little known. 

 Their nocturnal and subterranean life, combined with a shy and wary 

 disposition and diminutive size, often baffles the attempt of the natural- 

 ist to study, their habits, or even to secure specimens of the known 

 species. 



Contributions to our knowledge of American insectivora, since Profes- 

 sor Baird's treatise in 1857, are mainly due to Dr. Gill — "Synopsis of 

 Insectivorous Mammals," < Bull. U. S. Geol. and Geog. Surv., 2d ser., 

 No. 2, pp. 91-120, May 14, 1875; to Mr. J. A. Allen— '■ Catalogue of the 

 Mammals of Massachusetts, with a Critical Review of the Species," Bull. 

 Mus. Comp. Zool., Cambridge, i, No. 8, pp. 143-252, 1863; to Dr. Elliot 

 Coues—" Precursory Notes on American Insectivorous Mammals, with 

 Descriptions of New Species," in which several new sub-genera and 

 species derived from Professor Baird's MSS., written in 1861, are brought 

 out, and other species described by Dr. Coues, based on material not at 

 that time available. 



Genus Bi.aeina Gray. 



1851. Blarina, Gray, Pioc. Zool. Soc. Lond., 1861. (Type Soreot talpoides, 

 Gapper.j 



Generic Characters. — Teeth 32 or 30 (yj sub-genus Blarina, Gray, emend. ; 

 VI sub-genus Soriciscus, Coues). Ears small, the parts directed forward so 



