46 MAMMALIA ORDER III.INSECTIVORA. 



as well as in the temperate and tropical portions of Asia and North America, 

 and also in Africa, although they are represented in Madagascar only by a 

 single species, which is not improbably introduced. Although the majority 

 of the shrews are terrestrial and nocturnal in their habits, a few have taken 

 to an aquatic mode of life. They are all very shy and retiring, which is prob- 

 ably their chief protection ; and their food is entirely composed of insects, 

 worms, molluscs, and such like. Many shrews exhale a strong, musky odour ; 

 and at certain times of the year many of these animals are found lying dead 

 in the open, the cause of this mortality not being at present clearly ascer- 

 tained. Although it may seem a trivial character, the circumstance of the 

 teeth being stained reddish-brown, or simply white, serves to divide the 

 shrews into two groups. 



The typical shrews, or those forming the genus Sorex, belong to the group 

 with reddish teeth, and are specially characterised by having 32 teeth, the ear 

 well-developed, and the long tail covered with hairs of equal or nearly equal 

 length. The range of the genus includes North America, Europe, and Asia 

 north of the Himalaya ; its British representatives being the common shrew 

 (S. arauens) and the lesser shrew (S. pygmceus). Although shrews hibernate, 

 specimens have been occasionally seen running over the snow in mid- winter. 

 The Oriental shrews (Soriculus), which are the only representatives of the 

 red-toothed group in that region, are nearly allied ; but they have generally 

 only 30 teeth, and the first upper incisor has an inner cusp. Nearly allied 

 are two Mexican species constituting the genus Notiosorex, and characterised 

 by having only 28 teeth and no inner cusp to the first upper incisor, the tail 

 being also shorter. A larger American genus is Blarina, which is mainly 

 confined to the northern part of that continent, although a few forms descend 

 into Central America. Here the number of teeth varies from 30 to 32, while 

 the ear is truncated above and the tail short, the other characters being the 

 same as in Soriculus. The water-shrews (Crossopus), which are the last repre- 

 sentatives of the red-toothed section, have 30 teeth, small, non-truncated ears, 

 the long tail fringed on its lower surface with elongated hairs, and the feet 

 also fringed. The single species (C. fodiens) is thoroughly aquatic, and ranges 

 from England to the Altai Mountains. 



Certain shrews from Africa constituting the genus Myosorex are the first 

 representatives of the white-toothed section, and are specially characterised 

 by having well-developed ears, a long tail clothed with nearly or quite equal 

 hairs, and either 30 or 32 teeth, one minute species being unique in having 

 seven pairs of lower teeth. More numerous are the well-known musk-shrews 

 (Crocidura), differing from the last in having 28 or 30 teeth, and the long 

 tail covered with a mixture of long and short hairs. These shrews range from 

 South and Central Europe to Africa and Asia, reaching as far east as Amurland, 

 and being represented by one species in Madagascar. Out of some 80 species 

 one of the best known is the Indian musk-shrew (C. c<xrulea\ commonly 

 known as the musk-rat, of which the odour is so strong that every article of 

 food is rendered uneatable by the mere passage over it of the animal. The 

 Kirghiz shrew (Diplomesodon pulchellus) alone represents a genus differing 

 from the last by the shorter tail, the hairy soles of the feet, and the presence 

 of only 26 teeth. The two mole-shrews (Anurosorex), of which one is from 

 Assam and the other from Tibet and China, are peculiar in being of fossorial 

 habits, and may be distinguished by the absence of the external conch 

 of the ear, the short tail, the naked soles of the scale-covered feet, and the 

 velvety fur. The two remaining genera are aquatic, and thus occupy in this 



