﻿Dec, 1895.] 



SOREX FUMEUS. 



51 



Geographic distribution, — Boreal zone and locally the cooler parts of 

 the Transition zone in tlie eastern United States, ]S"ova Scotia, and Xew 

 Brunswick, west to Ontario and the Great Lakes. 



General characters. — About the size of Sorex richardsoni. Back with- 

 out distinct dark median area. Color smoky x^lumbeous gray. 



Color. — In autumn and winter: Back smoke gray, the hairs every- 

 where tipped with seal brown, j)roducing a finely grizzled appearance; 

 the dark tips slightly more conspicuous over rump and lumbar region, 

 less numerous on the sides, and disappearing entirely on the belly, 

 where the fur is pale broccoli brown. Everywhere the fur, which is 

 slate color at base, has a faint gloss. The result is a combination of 

 colors very hard to describe, but unlike that of any other Shrew occur- 

 ring in eastern North America. Tail indistinctly bicolor, seal brown 

 dorsally, yellowish white ventrally; feet yellowish white. In sum- 

 mer: Dull hair brown throughout, paler on the belly, and very slightly 

 darker on the back. 



Specimens in the dull, short summer coat are much like the average 

 8. personatus in color, but are usually paler, and may always be dis- 

 tinguished by a peculiar bluish cast. A specimen taken at. Lake 

 George, New York, July 10, 1892, has the full, dark autumnal pelage 

 appearing on the rump and buttocks in strong contrast with the short 

 pale fur on the rest of the body. 



81:%ai.—T\\^ skull of Sorex fumeus (PL TI, tig. 5) is a trifle smaller 

 than that of >S'. araneus or 8. richardsoni. The brain case is narrower 

 than in the other members of the araneus group, while the rostrum and 

 interorbital region are broader. The anterior opening of the infraor- 

 bital canal is larger than in >S'. richardsoni and placed farther back, 

 the posterior border of the ibramen lying over a point decidedly 

 behind the middle of the first molar instead of in front of the middle, 

 as in 8. richardsoni and 8. araneus. The lachrymal foramen is over 

 the space between the first and second molars. 



Teeth.— The teeth of 8orex fumeus resemble in a general way those of 

 8. richardsoni and 8. aranevs, but are smaller and less pigmented. 

 The posterior borders of the upper raolariform teeth are more exten- 

 sively excavated than in 8. richardsoni, thus resembling 8. araneus. 



The unicuspid teeth in profile (PL Y, fig. 5) are shorter and broader 

 than in the other members of the araneus group. The second and 

 third incisors are subequal, the second usually slightly the larger; the 

 fourth abruptly smaller than the third, and distinctly larger than the 

 canine; the first premolar very small, but visible from the outer side. 

 When slightly worn the unicuspid teeth show a peculiarity shared by 

 the members of the minutus group, but not often occurring in tbe allies 

 of 8. araneus; the points of these teeth wear away more rapidly on the 

 outer side, so that when seen in profile the less Avorn inner edge often 

 appears as a prominence suggesting an incipient secondary cusp pro- 

 jecting backward below the tip of the main cusp. In 8orex araneus 



