326 



INSECTIVORES. 



toothless young ; the number in each litter being usually five, six, or seven, but 

 occasionally more. 



In Ireland the place of the common shrew is taken by the lesser 

 shrew (S. pygmceus), which, although also found in England, is there 

 much more rare. It may be distinguished by its inferior size, and also by the 

 circumstance that the third tooth from the extremity of the upper jaw (the third 

 incisor) is not longer than the fourth. Like its larger cousin, this species has an 

 extensive range in Europe and Asia north of the Himalaya, but does not extend 

 across Behring Strait into America. 



In marked contrast to the wide range of these species is the 



restricted distribution of the Alpine shrew (S. afyinus), a species of 



rather larger size than the common shrew, and distinguished by the uniform 



coloration of the upper and under surfaces of the body. This shrew is only found. 



in the mountains of Central Europe. 



North American A variation in size comparable to that existing among the 

 Shrews. European members of the genus is likewise found in its North 

 American representatives, among which Bendire's shrew (S. bendirei) is the largest, 

 and Cooper's shrew (S. cooperi) the smallest form. Of the latter Dr. Hart Merriam 

 writes that " although underground life does not appear to be as attractive to it as 

 to its relatives the moles, yet it avoids too much exposure, and commonly moves, by 

 night and by day, under cover of the fallen leaves, twigs, and other debris that 

 always cover the ground in our northern forests. The naturalist well knows that, 

 however cautiously he may walk, the stir of his footsteps puts to flight many forms 

 of life that will reappear as soon as quiet is restored ; therefore, in his excursions 

 through the woods, he waits and watches, frequently stopping to listen and observe. 

 While thus occupied, it sometimes happens that a slight rustling reaches his ear. 

 There is no wind, but the eye rests upon a fallen leaf that seems to move. Presently 

 another stirs, and perhaps a third turns completely over. Then something evanescent, 

 like the shadow of an embryonic mouse, appears and vanishes before the eye can 

 catch its perfect image. Anon the restless phantom flits across an open space, 

 leaving no trace behind. But a charge of fine shot dropped with quick aim upon 

 the next leaf that moves will usually solve the mystery. The author of the per- 

 plexing commotion is found to be a curious sharp-nosed creature, no bigger than one's 

 little finger, and weighing hardly more than half a drachm. Its ceaseless activity, 

 and the rapidity with which it darts from place to place, are truly astonishing, and 

 rarely permit the observer a correct impression of its form. Whenever a tree or a 

 large limb falls to the ground these shrews soon find it, examining every part with 

 great care, and if a knot-hole or crevice is detected, leading to a cavity within, they 

 are pretty sure to enter, carry in materials for a nest, and take formal possession. . . 

 Not only are these agile and restless little shrews voracious and almost insatiable, 

 consuming incredible quantities of raw meat and insects with great eagerness, but 

 they are veritable cannibals withal, and will even slay and devour their own kind." 

 The marsh-shrew (S. palustris) from the Rocky Mountains, together with the 

 swimming shrew (8. hydrodromus) from one of the Aleutian Islands, differ from the 

 other members of the genus in having their feet provided with fringes of long hair 

 to aid them in their aquatic life. 



