54 MAMMALIA. 



One March, many years ago, when shding down hill on the 

 crust (the snow then being over three feet in depth) Dr. C. L. 

 Bagg and 1 observed at different times several dark objects which 

 at a distance looked like little balls of fur. (3n coming nearer we 

 discovered that these apparently round objects were Star-nosed 

 Moles, trying to bore through the icy crust. They had evidently 

 been moving about on the surface till alarmed by our approach, 

 when, having wandered away from the holes through which they 

 came up, they at once set to work to perforate the crust, but, owing 

 to its unusual hardness, did not succeed in time to make good their 

 escape. We captured two or three and brought them home. 



The reason that they are not more often seen here in winter is 

 easily explained. They do not at any time travel much upon the 

 surface, and even when thus engaged their sense of hearing is so 

 acute that they detect the approach of an enemy while yet at a 

 distance, and disappear at once into the snow. All winter long 

 one sees upon the snow many small footprints, that are designated, 

 collectively, as mice, mole, and shrew tracks. I can distinguish, 

 with considerable confidence, those of Hespcromys, Blarina, and 

 Sorcx, but who will venture to affirm that he can name the species 

 that makes each of the others ? 



The tail of this species becomes enormously enlarged during the 

 rutting season, which circumstance led Dr. Harlan to describe a 

 specimen taken during this period as a distinct species, which he 

 named Coiidyltira macroura.'^ I have taken specimens as late as 

 the middle of November whose tails measured 12mm. (.47 in.) in 

 diameter. When in this swollen condition there is a marked con- 

 striction at the base, which causes the tail to appear as if strangu- 

 lated. Two or more litters are produced each season. 



The scent glands of this animal secrete a thick creamy material 

 of a greenish yellow color that has a powerful and very disagree- 



* Fauna Americana, 1825, p. 39. 



