NO.llOl. PROCEEDINGS OF THE NATIONAL MUSEUM. 59 



The third tooth of the. iipx)er jaw following the large incisor is more elongated 

 than in the true Talpa Townsendii; the posterior cusps of the 7th and 8th lower 

 teeth, althongh distinct, are smaller than in T. townsendii and there is no distinct 

 internal hasal margin connected with the cnsp. 



My study of the group leads me to believe that the peculiar coloration 

 is merely au individual variation. Tlie characters ascribed to tlie teeth 

 could, only be considered important if the teeth were unworn. The 

 changes due to use are greater than those here employed for specific 

 differentiation. 



CHANGE OF PELAGE IN SCAPANUS. 



The change of pelage in this genus appears to begin on the breast 

 and to extend thence to the head and back and finally to the belly, on 

 which the new hair intrudes both from the breast and the sides. 



The specimens at command are not sufficient to make entirely plain 

 the dates at whicli the changes begin and are completed in tlie several 

 species. In southern Washington and northern Oregon the fall change 

 of iS'. toirnsendi, probably begins about the first of October. One speci- 

 men from Tenino, Washington, has the entire new pelage October 19, 

 and I may conclude that, in males at least, the molt ends about this time- 

 In northern Oregon the change has not affected the belly at this date, 

 so that the molt is probably not completed here before the first of 

 November. 



The dates for S. callforuicus are probably somewhat later, and in 

 southern California the fall molt probably begins as late as November 

 1. In a male obtained in Marin County November 23 and a female 

 obtained November 27, the belly still retains the old fur, so that in this 

 part of northern California the fall molt can scarcely be completed 

 until after the 1st of December. 



In relation to the spring molt, we find the following: A si)eciinen of 

 S. toicnsendi from Tacoma, Washington, taken in May, has the new fur 

 on the breast and head and along the middle of the back; there are 

 also a number of small irregular patches of new hair on the belly. 



Of />'. calif or nicus, a female from Nicasio, California, captured May 10, 

 a male May 15, another male May 22, and a second female June 20, all 

 have the appearance of having completed the molt. It is quite proba- 

 ble, however, that they have not yet commenced, as appears from the 

 fa(;t that a female from the same locality, taken May 29, has the new fur 

 developed only on the breast, and is just starting on the head and hinder 

 part of the back. A feniale from Cazadero, Sonoma County, taken 

 July 5, has shed on the neck, head, and most of the back, but not on 

 the rum]), sides, or belly. 



In this specimen the old and new fur are so closely alike in color 

 except on the bieast that the line of demarkation can only be detected 

 by very close scrutiny. Another specimen (a female?), taken at Nicasio 

 July 12, still has a small patch of old fur on the sides of the belly, and 

 one from Gualala, taken July 14 (marked male, but probably female), 



