NO. 1101. rnOCEEDINGS OF THE NATIONAL MTJSEVM. 37 



SEASONAL CHANGES OF PELAGE. 



The winter fur in ScaJops is longer and grayer in color than the sum- 

 mer fur. 



The males of this species in the northern part of the range shed the 

 winter fur in May and the summer fur in October. The females com- 

 monly undergo the changes during the same months, but the process is 

 frequently retarded in spring from causes connected ai)parently with 

 reproduction. Thus a female from the Central Park, Xew York ( Amer. 

 Mus. Coll., 1010), obtained July 12, presents the woin winter pelage, 

 with the si)ring x>elage concealed beneath it. Another female (Merr. 

 Coll., 2750) from Laurel, Maryland, obtained June 23, has the long 

 winter fur on the middle of the back, while the rump and shoulders are 

 clothed with the shorter fresh spring fur. In still another specimen, 

 an adult female from Washington City (Dept. Agric. Coll., 22S5S), 

 obtained July 1, though the long winter fur has been shed from the 

 greater part of the back, it still remains on the anteiicn- ])ortion. 



The time of the spring change appears to vary considerably with the 

 latitude, and specimens from the Northern States begin to shed later in 

 spring than those from the South. A nursing female from Oak Lodge, 

 Florida, in Mr. Bangs' collection, obtained February 21, has new fur 

 on the lower surfaces, except a narrow band across the abdomen. 

 There is certainly no retardation in this case. A male from the same 

 locality, taken F^'ebruary 20, apparently has new fur on the shoulders. 



Two fall specimens (males) from Padre Island, Texas, taken Xovember 

 and 9, have not completed the molt. Hence it may be supposed that 

 the fall change is somewhat delayed at the South. 



The winter fur, as already intimated, is much longer than the sum- 

 mer fur and darker in color. 



INDIVIDUAL VARIATIONS IN DENTITION AND COLORATION. 



A considerable number of the skulls of Scalops which I have exam- 

 ined possess greater or less abnormalities of dentition. These usually 

 consist in the retention or suppression of teeth which are normally 

 absent or present respectively. One of the most striking of these 

 deviations is the presence of an extra lower premolar in front of the 

 usual ones. In two cases of adult skulls which have come under my 

 observation this tooth is present on both sides, and in another instance 

 on one side only. In one of the skulls this extra tooth is large and 

 prominent, but in the others it is filiform. It is perhaps doubtful 

 whether this sliould be regarded as an abnormality. In all the quite 

 young skulls which I have examined, this tooth is present usually on 

 both sides of the jaw. I have been unable to detect any milk tooth 

 corresponding to this small extra tooth, but as this would in any case 

 be extremely minute it has probably escaped my scrutiny. It may be 

 remarked further in this connection that many jaws in which this tooth 

 can not be detected exhibit at the point where it should occur a small 



