66 



INSEOTIVOEA 



the hind feet enlarged and turned somewhat outward ; in one 

 species a longitudinal ridge of stiffened hairs along under surface 

 of tail ; ear small, completely hidden in the fur, the meatus 

 closed by two valves, one of which lies on inner surface of 

 •antitragus, the other on inner surface of conch ; habits aquatic. 



Remarks. — In its external form, slight reduction in the 

 number of teeth, and in the noticeably prehensory adaptation 

 of the upper incisors and unicuspids, the members of the genus 

 Neomys are distinctly more specialized than the species of Sorex. 

 They retain, however, the primitive form of the third lower 

 molar and lower premolar characteristic of Sorex, these teeth 

 showing no tendency to the more highly modified structure 

 found in Crocidura. The members of the genus Neomys are the 

 only European shrews specially adapted to aquatic life. They 

 are at once recognizable by their dense, velvety fur, and large, 

 distinctly fringed hind feet. In the commonest and most widely 

 distributed species the tail is provided with a keel of stiffened 

 hairs, a character not found in any other European shrew. 



KEY TO THE EUROPEAN FORMS OP NEOMYS. 



Tail with median keel of stiffened hairs extending 



entire length of under surface N. fodiens, p. 66. 



Underparts whitish or yellowish, occasionally 

 brownish (Continental Europe except Iberian 



Peninsula) X. f. fodiens, p. 69. 



Underparts usually brownish (England and Scot- 

 land) X.f- bicolor, p. 73. 



Tail without keel. 



Length of tail 47 to 53 mm. ; hind foot 16 to 



17 mm. (Alps and Pyrenees) N. milleri, p. 78. 



Length of tail 55 to 61 mm.; hind foot 16 '8 to 



18 mm. (Northern and central Spain) N. anomalus, p. 81. 



NEOMYS fodiens Schreber. 

 (Synonymy under subspecies.) 



Geographical distribution. — From Norway and England to the 

 Pyrenees, northern Italy and western Siberia. Northern and 

 eastern limits of range not known. 



Diagnosis. — Tail with keel always present ; feet very con- 

 spicuously fringed; hind foot usually more than 17 mm. ; lachry- 

 mal foramen opening over posterior half of m 1 ; anterior upper 

 incisor robust. 



External characters. — Fur very dense, its depth at middle of 

 back about 6 mm. in summer, 9 mm. in winter, its texture soft 

 and velvety, this particularly noticeable on underparts ; a 

 few longer hairs usually present on flanks and rump. Eyes 

 small and inconspicuous ; ears completely hidden by the fur. 

 Muzzle less slender than in Sorex araneus, the median ridge on 

 upper lip with distinct wart-like outgrowth which fits between 

 points of upper incisors when mouth is closed. Feet larger than 



