1915.] 



IN-TKODUCTION. 



11 



PELAGES AND MOLTS. 



The hair of all American moles is fine and silky, producing a soft 

 and velvetlike pelage. In Scalopus, Scapanus, and Parascalops the 

 hairs are nearly equal in length and there is no distinct underfur. 

 In Condylura some of the hairs are distinctly longer and coarser than 

 the major portion, the latter forming an underfur, and the whole 

 producing a pelage much less velvetlike than that of any other 

 genus. In Neurotrichus the condition of the pelage is somewhat as 

 in Condylura; the fur is shorter, however, and the underfur difficult 

 to detect. 



The basal pelage reveals a series of transverse vermiculations, most 

 pronounced in Scalopus and Scapanus, least in Neurotrichus; in aU 

 genera these markings are more noticeable in the fur on the back, less 

 on the ventral parts. Microscopic examination shows that these 

 vermiculations are due to structural as weU as chromatic differences. 

 Each hair consists of normally pigmented, gray, cyHndrical sections, 

 1 to 2 mm. long, alternated with finer flat sections, 0.2 to 0.5 mm. 

 long and unpigmented, or with the pigment reduced to a small amount 

 of yellow. Each one of these fine, flat sections acts as a hinge upon 

 which the hair bends; this in part produces the velvethke texture of 

 the pelage and permits the hair to be rubbed either forward or back- 

 ward with little friction — a distinct advantage to a subterranean 

 mammal. The vermiculations usually show more clearly in worn 

 pelage than in fresh. The young of Scalopus, Scapanus, and Para- 

 scalops, in. their first winter pelage, are more grayish than adults; of 

 Condylura, paler and more brownish. Winter pelage of adults of all 

 moles is usually darker than that of summer; worn pelage is faded 

 and frequently more brownish than the fresh. The color of speci- 

 mens retaiued in a cabinet or storage case for a few years usually 

 fades, becoming more brownish than that of recently killed animals. 



TIME OF MOLTING. 



There are two molts annually in Scalopus, one m spring and the 

 • other in faU. Throughout most of the range of the genus the 

 spring molt is usually completed by the last of May or the first of 

 June; the fall molt, in the northern haK of the range, by the first 

 week in October; in the southern part of the range the fall molt 

 naturally occurs later in the year, and the spring molt earlier than 

 farther north. The winter pelage of breeding females becomes worn 

 early in the season, but, as has been suggested by True,^ the actual 

 molting in such individuals may frequently be delayed. Examina- 

 tion of a large series of specimens from Washington, D. C, shows that 



1 Trae, F. W., Proe. U. S. Nat. Mus., vol. 19, p. 37, 1896. 



