ORDER INSECTIVORA. 

 INSECT EATERS. 



Representatives of this large order are found throughout the greater 

 portion of the temperate and tropical world, except, so far as known, in 

 Australia and South America. All of its members are comparatively 

 small animals. The greater number are terrestrial, although a few 

 are arboreal and others natatorial. They are nearly all of them noc- 

 turnal animals; some are covered with spines, but the majority are 

 thickly furred. They are largely, but by no means strictly, insectiv- 

 orous ; most of our species eat great numbers of earth-worms and young 

 Mice when they can get them; while some species, like the European 

 Hedgehog, have such a varied diet as to be practically omnivorous. 



While in all known species, incisors, canines, premolars and molars 

 are present, most of them are not clearly differentiated and for conve- 

 nience all single pointed teeth are called unicuspids. The number of 

 teeth varies in different species, some having as high as 44. In our 

 Shrews belonging to the subfamily Soricince the ends of the teeth are 

 colored red, while in the Crocidurince, and Old World subfamily, the 

 teeth are entirely white. There seems to be a tendency in many of 

 the members of this order towards the disappearance of milk teeth. 

 In the species belonging to the genus Sorex, for example, there are but 

 seven milk teeth and none of them ever become functional. These 

 animals are characterized by having an elongated snout, with the upper 

 lip extending considerably beyond the lower; clavicles are present in 

 all except the peculiar African genus Potamogale. The position of 

 the mammary glands and number of teats vary in different species. 

 The uterus is bicornate and the placenta discoidal and deciduous. The 

 caecum is absent in our species. The majority possess glands contain- 

 ing a strong, disagreeable, musky secretion, which is supposed to be 

 a means of protection, as it is claimed carnivorous mammals will 

 rarely eat them. The location of these glands varies in different species ; 

 in our Shrews they are usually located on the sides of the body behind 

 the axilla. The toes are armed with claws which in many species are 

 highly developed for digging. Shrews do not hibernate and are active 

 all winter. 



On the North American continent the order is represented by two 

 families: Soricida, Shrews, and Talpidce, Moles, comprising more than 



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