25° 



THE OPEN COUNTRY 



normal on account of the damage done by these larva?, which in 1759 and 1802 

 swarmed in the sheep-farms of Tweeddale, devouring grass to the root over patches 

 more than a mile square ; again, in 1884, larva? was such a pest in Glamorgan that 

 the surface herbage was burnt to destroy them. Equally injurious is the caterpillar of 

 the turnip moth (Agrotis segetum), which feeds on cabbages, turnips, swedes, lettuces, 

 and other vegetables, and hibernates, to begin its career of destruction early in the 

 spring. When touched, it rolls itself up ; by day it hides under stones or in the 

 ground, creeping out at night to feed. It is striped brown and grey, sometimes 

 tinged with pink, with three dark lines on the back, the middle one double. The 



■ 



-•• 



SIX-SPOTTED BURNET MOTH 



moth, which should be looked for from May to July, inhabits all the countries of 

 Europe, and is very common in Germany ; it is If inches in wing-spread, 

 the front-wings being brownish grey, dark at the hind-margin, with three 

 toothed cross-lines and two black-edged spots, while the hind-wings are whitish 

 with brownish nervures, those of the female bearing a grey dust. Another injurious 

 species is the silver gamma moth (Plusia gamma), which, like the last, flies in the 

 sunshine and is 1 f inches across. Nearly in the middle of its violet wings it has a silver 

 mark, resembling the Greek letter y or the ordinary Y, and is thus easily distin- 

 guishable. The caterpillar lives from April to September on nettles, dead-nettles, 

 turnips, mangold, clover, or other plants, including oats and especially hemp, to 



