496 Life-histories of Northern Animals 



This elaborate construction is amply justified by the facts 

 that the nest is not a mere nursery. It is the home of the family 

 the whole year round, and must be proof against rain, frost, 

 and flood, as well as hidden from innumerable enemies. 



STORE- Not far from the home-den, and usually connected with 



it, is the storeroom filled with various seeds and grasses 

 (never roots), for the Deermouse does not hibernate even in 

 the coldest weather, and therefore lays up in times of plenty a 

 store of food to last it through the evil days ahead. 



MATING All the evidence at hand goes to show that the Deer- 



mouse pairs; that usually the male helps his partner to pre- 

 pare the nest and care for the young, but that there are cases 

 in which the male abandons the female as soon as the joys of 

 the mating season are banished by the responsibilities. 



Pairing takes place in late winter, and the two together 

 construct the nest. 

 GESTA- Gestation I find to be 23 days in the White-footed Deer- 



mouse of Connecticut; it is probably the same in this species. 

 The earliest brood comes about April i, in Manitoba, and is 

 succeeded by another every sixty days till snow time; thus a 

 pair may have 4 litters in a season. 



The young are usually 4 or 5 in number, but 3 are often 

 seen, especially for the first brood of a young mother; I once 

 found 7 embryos in a mature female, though she had but 6 teats. 



When the nest is disturbed so that the mother runs out, 

 she commonly carries ofl^ some or even all of her brood attached 

 to her teats. This, however, is not her regular mode of carry- 

 ing them about, but is rather due to the fact that the young 

 when very sm.all attached themselves firmly to the teat, almost 

 in marsupial style, and the mother has not time to disengage 

 herself if suddenly driven forth. Most of the Deermice carry 

 their young in the mouth, one at a time, when they move them, 

 just as a cat does her kittens. 



Near Hamilton, Montana, on the evening of September 4, 

 1902, I found in one of our horse panniers a Deermouse 



TION 



