768 MANUAL OF ZOOLOGY. 



Lastly, in the curious genus Urotrichns (sometimes referred 

 to the Myogalid(Z\ of Japan and the north-west of America, 

 the nose is long and cylindrical, terminated by a naked fleshy 

 bulb, and extremely sensitive, the tail is moderately developed 

 and hairy, and the fore-feet are adapted for burrowing. Allied 

 forms have also been recently discovered in North China and 

 Thibet 



Fam. 2. Potamogalida. This family merely requires to be 

 mentioned as founded for the reception of a single genus 

 (Potamogale), comprising only a single species (P. velox). This 

 animal is a curious Otter-like Insectivore, which leads a semi- 

 aquatic life, to which end it has a long compressed tail. Cla- 

 vicles are also entirely wanting. It is confined to the west of 

 Africa. 



Fam. 3. Soridda. The Soricidce or Shrew-mice are distin- 

 guished by having the body covered with hair, and the feet not 

 adapted for digging ; whilst there are mostly external ears, and 

 the eyes are well developed. The tail is nearly naked, and 

 scaly ; the central upper and lower incisors are very large ; the 

 tibia and fibula are united; and there is no caecum. Of all 

 the Insectivora, no division is more abundant or more widely 

 distributed than that of the Shrew-mice, their range extending 

 over North America and the whole of the Old World, In 

 general form and appearance the Shrews very closely resemble 

 the true Mice (Muridcz)^ and the Dormice (Myoxida), but they 

 are in reality widely different, and must not be confounded 

 with them. The Common Shrew (Sorex vulgaris\ the Garden 

 Shrew \Crocidura araned), and the Water-Shrew (Crossopus 

 fodtens) are well-known British species of this family. The 

 smallest known Mammal is one of the Shrews (Sorex Etrus- 

 cus\ which is not more than two and a half inches in length, 

 counting in the tail. 



Ths Desmans or Musk-rats, forming the genus Myogale, 

 are sometimes placed here, sometimes in the family of the 

 Talptdce, and are often raised to the rank of a distinct family 

 (Myogalida). They have the nose prolonged into a kind of 

 flexible proboscis, whilst the feet are webbed, and the tail is 

 compressed, thus adapting the animal for a semi-aquatic life. 



The dental formula is 



. 2 2 I T q tj 3 ? 



i - ; c - ; pm * ; m - - = 44. 

 22 i i 55 33 



The central incisors and the lateral lower incisors are very 

 large and pyramidal ; and the hind-legs are longer than the 



