392 SYSTEMATIC ZOOLOGY 



to the genus Lepus ; the common hare of Europe is Lepus 

 timidus ; the most common rabbit in the United States is 

 Lepus sylvaticus, the wood rabbit or Molly cottontail, which 

 is our nearest relative to the European rabbit, Lepus cuniculus. 

 The most common distinction made between the rabbits and 

 the hares is that the former burrow and the latter do not. In 

 the western United States we have several interesting species, 

 known popularly as jackass hares or jack rabbits ; their speed 

 is truly marvelous. ' Related to the rabbits are the pikas, about 

 eighteen centimeters long, with almost no tail at all. They are 

 found in the mountains of Asia, Europe, and western North 

 America ; here they are popularly called conies. 



Order 6. Insectivora 



The Insectivora (Lat. inseetum, insect, and vorare, to devour) 

 are small mammals, usually having five toes to the feet, armed 

 with claws, resembling some of the rodents in general external 

 appearance, but readily distinguished from them by the denti- 

 tion, which here is complete, all four kinds of teeth being 

 present. The permanent teeth appear early, so that the milk 

 teeth are rarely functional. The body is usually covered with 

 soft fur, but in some sharp spines develop also. The testes are 

 always internal. A very characteristic feature of the Insectivora 

 is the snout or muzzle, which is always more or less elongated 

 and extends much farther forward than the lower jaw. The 

 eyes are generally small and in some species almost entirely 

 concealed by the fur. They are mostly nocturnal in habit ; 

 some burrow in the ground, a few are amphibious or aquatic, 

 and some are arboreal. They all feed on insects and other 

 small animals such as worms, and are widely distributed, being 

 unknown only in South America and Australia. 



The largest member of the order is found in equatorial Africa. 

 It measures about thirty centimeters in length, with a tail almost 

 equally long ; the tail is laterally compressed and serves as an 

 efficient organ for swimming, as the species is amphibious. 

 The moles, which are found in the temperate regions of the 

 eastern hemisphere and North America, have the paws well 

 adapted to digging, and make very elaborate and extensive 



