4 Adams, Epidemic of tJie Coiinnon and Lesser SJirezv. 



Of course, shrews may be found in coppices all the 

 year round, though I think they often leave this cover to 

 breed in the open fields, as I find that during the breeding 

 season far fewer are caught in the coppices and hedges 

 than in the rough patches of coarse grass in the open. 



It is not known how many litters a single female pro- 

 duces during the breeding season, but it is certain that 

 more than one are reared, as I have trapped pregnant 

 females which had evidently suckled previously. In the 

 case of the Common Shrew, I have examined four females 

 with 8 embryos, two with 7, and one with 4 ; of the 

 Lesser Shrew, one with 8, one with 6, and one with 5. 

 As the breeding season lasts from the beginning of May 

 till late in November, it would seem improbable that the 

 same individuals continue breeding during the whole of 

 this time ; and in fact there is every reason to conclude 

 that the breeding is kept up during the season by a 

 succession of breeders coming into use at different times, 

 since on July 5th and on November 21st of the present 

 year (1909) I captured females, which, though recently 

 impregnated, had not previously littered. The former 

 showed only slight traces of conflict and the latter none 

 at all, which immunity I have never observed with adults 

 earlier in the season, and which I account for by sup- 

 posing that adult competitors had died out — in which 

 supposition I am supported by the evidence in the 

 Table, column 3. (See pp. 12, 13.) 



As winter draws on the survivors of the "epidemic" 

 seek the shelter of the hedges and live in burrows. I do 

 not think they often make burrows for themselves, but 

 make use of those of mice and voles. By the way, it does 

 not seem to be known exactly where they sleep in winter. 

 One would imagine that they make nests somewhere in 

 the burrows, but I have never been able to find any. 



