THE SHREW FAMILY 



(Soricidw) 



HREWS constitute the largest family of the Insectivores, and include the 

 smallest of all mammals. These tiny animals, some of them but little more 

 than three inches long, are sometimes mistaken for Moles and, more often, 

 as they scuttle through the grass or fallen leaves, for Mice. In the gardens 

 and in the woods, in the dry fields and in swamps and marshes, on the plains 

 and in high mountains, a Shrew of some sort is usually to be found. 



Many of the Shrews are hardy little creatures, and some of the northern 

 species may be seen abroad even in the cold of an Arctic winter. Although 

 they are classed among the insect-eating mammals, insects are not their only 

 food. Dr. D. G. Elhot says: "They do not confine themselves by any 

 means to an insectivorous diet, but devour worms, small birds or any scraps 

 of meat that fall in their way." 



The Shrews are characterized as very small Insectivores with mouse-like forms and long 

 slender snouts. They have well-furred bodies and well -developed tails usually covered with 

 short hairs. The eyes and ears are small ; the feet are slender or only slightly widened ; the 

 skull has no zygomata. Most of the Shrews are terrestrial, but a few are aquatic. This 

 family contains more than half the representatives of the order. 



For present purposes, the Shrews of America may conveniently be divided into four 

 groups, namely : Long-tailed Shrews (genus Sorex) : Small Shrews (Microsorex) ; Short- 

 tailed Shrews {Blarina and Notiosorex); and Swimming Shrews {Neosorex and Atopliyrax). 



COMMON SHREW 

 Sorex personatus /. Gcoffroy 



Other Names. — Long-tailed Shrew, Cooper's Shrew. 

 Masked Shrew. Shrew Mouse. 



General Description. — A very small mamnial with 

 a sharp nose, minute eyes, and fairly long tail. Ears 

 small and nearly hidden by hair of head ; teeth sharp 

 and stained with chestnut at the tips; body slender; 

 legs short and slender ; pelage thick and soft. An 

 active, quick-moving little animal. 



Dental Formula.— Incisors. ^-^ ; Canines, ^^ : Pre- 



molars, ^ 



Molars, ^-^=32. 

 3—3 



Pelage. — .Adults : Sexes identical ; seasonal varia- 

 tion slight. Above, sepia-brown and occasionally chest- 

 •_nut ; below, ashy-gray or brownish-ash ; tail above 

 blackish, below whitish. Young : Like adults. 



Measurements. — Total length, 4 inches ; tail ver- 

 tebrae, 1.5 inches; hind foot. .5 inch. Weight, 2.85 

 grammes, or 43.95 grains. 



Range. — North .America from New England to 

 Alaska, e.xcept the southern Rocky Mountains and Cas- 

 cade Sierra systems ; south in Alleghenies to Tennessee 

 and North Carolina. 



Food. — Insects, and any animal food it can secure. 



Remarks. — Six genera go to make up this group, for 

 specialization along several main lines has taken place. 

 The genus Sorex with 42 species and subspecies is easily 

 the largest group, and most of its members vary super- 

 ficially only in color and somewhat in size. The related 

 genera vary more widely in proportions of parts and 

 in special adaptations to be discussed in the synopsis 

 of these forms. There are 66 species and subspecies 

 in all. 



Related Species 



Common Shrew. — Sorex personatus personatus I. 

 GeofFroy. Typical animal as described above. North 

 America from New England to Alaska, south to Ten- 

 nessee and North Carolina in the Alleghenies. but not 

 found in the southern Rocky Mountains and the Cas- 

 cade-Sierra systems. 



Richardson's Shrew. — Sorex ricluirdsonii Bach- 

 man. Larger, back very dark brown, sides fulvous- 

 brown, under parts ashy-plumbeous. Plains of Saskat- 

 chewan, and in Minnesota and Wisconsin, 



Arctic Shrew. — Sorex sphai/iiieola Cones, Size 

 medium ; above, dark seal-brown, grayish-brown below. 



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