188 CLASS MAMMALIA. 



Shrews, as we have observed above, are always provided 

 with it. 



Finally, the completion of this system of organization, 

 by virtue of which the Desman, renouncing, as it were, 

 the attributes of a quadruped, comes to partake, with the 

 fish, their natural element, is found in the transformation 

 of its organs of locomotion into genuine oars. Its limbs are 

 extremely short, and partly involved under the teguments of 

 the trunk, and the toes, which terminatethem, are connected 

 by membranes. The tail, in fine, as well as every other 

 part, is accommodated to the same system, being flattened 

 on the side, and contributing, by this conformation, to fa- 

 cilitate the operation of swimming. 



This co-relative disposition of all the parts of the Des- 

 man ; this concordant adaptation of all its forms, to con- 

 stitute it an aquatic animal, exercises, as may be well sup- 

 posed, the most imperious control over its habits and 

 propensities. The Desmans, in truth, pass the most con- 

 siderable portion of their lives in and under the water. 

 Never, of their own accord, do they seek a dry place; and 

 if they proceed from one pond to another, it is only when 

 they meet with subterraneous channels, or ditches filled 

 with water, to conduct them. 



They choose, by preference, ponds, lakes, all kinds of 

 dormant waters, but more especially inundated places, sur- 

 rounded by elevated banks, as their general habitations. 

 They make there a sort of burrow, the entrance to which is 

 under the water. From this entrance, they commence 

 their operations ; they dig on, gaining, by degrees, in 

 height, elevating their work in multiplied and lengthened 

 windings, so as to embrace, at times, an extent of more 

 than one-and-twenty feet. Thus, there is but one part of 

 their burrow under the water ; there they live, either 

 singly, or in a monogamous state, according to the season. 



