162 THE ZOOLOGIST. 



Stewartry of Kirkcudbright, are also reported to be more or less 

 affected. In Eoxburgh and Dumfries the plague is estimated to 

 have extended over an area of from 80,000 to 90,000 acres. 



The so-called Field Mouse, or, more properly, Field Vole, 

 which has thus proved so destructive to the pastures is recognised 

 as Arvicola agrestis (Linn.). This pest was observed to be more 

 than usually numerous in the autumn and winter of 1890, and to 

 multiply rapidly in the following spring and summer. The mice 

 apparently first attacked the boggy and rough pasture lands, and 

 as the latter became foul or exhausted, the attack spread to the 

 barer lea land and even to the heather. Damage to young trees 

 in enclosed plantations has also been reported, but this may 

 probably be attributed to the attacks of the Bank Vole, Arvicola 

 glareolus (Schreber). [See p. 166.] 



Sheep are reported to be suffering severely in the districts 

 affected, and large portions of many flocks have been removed to 

 winterage, wherever that can be found. Hay and artificial foods 

 are necessarily being used for feeding stock on many hirsels. 

 Arable land is, it is stated, not appreciably affected, but fears are 

 entertained that the seed-corn may be attacked, especially in low 

 lands where the mice can work their way up the furrows. 



A preponderance of opinion amongst farmers is reported 

 tracing the cause of the present outbreak to the scarcity of Owls, 

 Kestrels, Hawks, Weasels, and other vermin. All these animals 

 are to be ranged among the natural enemies of the mice, and 

 even Crows may be placed in the same category. A climatic 

 cause of very considerable importance is also pointed out, in the 

 fact that the peculiarly luxuriant hill-growth in the winter of 

 1890-91, coupled with the mildness of that season in Scotland, 

 afforded the Voles unusual advantages in the shape of shelter 

 from their natural enemies, and favoured their increase. 



Pits or traps, such as are resorted to on the Continent, are 

 reported to have proved of but little use as remedies on this 

 occasion, and although thousands of Voles have been killed by 

 men with spades and dogs, this method can only be of limited 

 avail under the circumstances. The Inspectors concur in repre- 

 senting that, in the absence of a natural remedy, the general 

 feeling favours the burning of the affected ground, as offering a 

 more effective means of possibly exterminating the pest. 



