MAMMALS. 77 



(Archibuteo lagopus) on the wing at the same time, and 

 the short and long-eared Owls were observed in still 

 larger numbers. By the middle of April the herbage 

 was so much impaired that the Voles themselves began 

 to feel the want of food, and the occurrence of severe 

 frost, with a sprinkling of snow, about the middle of the 

 month, completed their discomfiture. Many died of 

 starvation, and by the end of May they had mostly dis- 

 appeared. When the Committee of the Farmers' Club 

 made their inspection, they found that fully one-third 

 of the pasture in the places visited had been destroyed. 

 The true bog-grass especially, on which the sheep 

 mainly depend in April and May, had been eaten down 

 to the roots. The ground was strewed with dried stalks 

 and blades, mixed with tufts of fur, limbs, and other 

 remains of the depredators. The sheep were in deplor- 

 able case ; several had died ; and the emaciated ewes, 

 too weak to make good nurses, suckled their lambs with 

 difficulty. Numbers of these had perished in con- 

 sequence, and the survivors were poor and weakly." 

 It is scarcely necessary to add that the food of the Field 

 Vole consists of vegetable matter of all kinds (especially 

 grain, which it obtains by biting through the stalk above 

 the root), and that it lives in burrows in the ground. 

 In these it lays up winter stores of grain and berries, 

 and feeds on them when mild weather comes from time 

 to time, but, otherwise, hibernates through the winter 

 uninterruptedly. The nest is in one of the burrows; 

 the female litters five or six times in the course of a 

 year, and has from four to eight young each time, so that 

 it is not difficult to account for the enormous increase when 

 their numbers are not kept in check by owls, etc. In 



