1908.] MAMMALS. 243 



big; Calling River; 25 and r>() miles above Pelican Rapid; Pelican 

 Rapid; Cascade Rapid; Mountain Rapid; Fort Chipewyan; Slave 

 River, 10 miles below Peace River; Smith Landing; Fort Smith; 

 Slave River, 100 miles below Fort Smith: Fort Resolution; Trout 

 Rock, 25 miles south of Fort Rae; Fort Rae; Grandin River; Lac St. 

 Croix ; Fort Franklin, Great Pear Lake ; Fort Providence ; Fort Simp- 

 son; mountains near month North Nahanni River; Fort Wrigley; and 

 Fort Norman. AVe took specimens in nearly all kinds of situations, 

 but found the animals most common in marshes and about the mar- 

 gins of muskeg ponds. They enter the storehouses of the trading 

 posts freely, especially in winter, and several were taken in such 

 situations. Embryos were noted in only two instances, as follows: 

 Fort Chipewyan, June 3, 1901, 10 embryos; mountains near mouth 

 of Nahanni River, July 18, 1903, 6 embryos. The side glands, which 

 apparently are to be found on all adult male shrews in the summer 

 or breeding season, are small in this species, occupying a space only 

 2 or 3 mm. in length. They are covered with short stiff hair of 

 about the same color as the surrounding fur. They are conspicuous 

 only during the breeding season, probably serving a sexual purpose, 

 are barely discernible in autumn, and can scarcely be. detected, in 

 (bis species, at least, in winter. 



The series taken at Fort Franklin late in September, 1903, com- 

 prises specimens in both summer and winter pelages, showing the 

 approximate date of the autumn molt in that region. At Fort Simp- 

 son a small series in full winter pelage was taken in the late autumn 

 and early winter of the same year. During the winter their tiny 

 tracks and tunnels were often seen in the woods, and when the tem- 

 perature stands at 40° below zero and constant motion is necessary 

 to keep one from freezing, one can not help wondering that this tiny 

 creature manages to sustain life. 



In addition to the large series collected by our party, 1 have ex- 

 amined a collection of nearly a hundred specimens of shrews (skins 

 and alcoholics) sent to the Smithsonian Institution by various mem- 

 bers of the Hudson's Bay Company years ago, and which has never 

 before been critically studied. As might be expected, the collection 

 contains much interesting material, and supplements our series ad- 

 mirably. It contains about 40 specimens of S. personatus from the 

 following localities: Cumberland district. Saskatchewan; Fori Reso- 

 lution: Fort Rae: Big Island. Great Slave Lake; Fort Simpson; 

 Fort Liard; Mackenzie River below Fort Good Hope: Fort McPher- 

 son: mouth of Porcupine River; Fort Anderson: mouth of Ander- 

 son River; and [south end of J Franklin Bay. 



Ten adult specimens from the Athabaska average in measurements: 

 Total length ( .>r>.<;. tail vertebrae 38.9, hind foot 12; ten from Great 

 Slave Lake, 101.0. 38.8, 12; ten from Fort Franklin. 96.7, 38.1, 11.!). 



