234 LEPIDOPTERA. 



ance. Dr. F. D. Wheeler says : " It appears to inhabit the 

 highest mountain peaks on the south side of Loch Eaunoch, 

 Perthshire, occurring as low as 2300 or 2100 feet above the 

 level of the sea, where the vegetation is very scanty. It 

 hides in the day under stones, among heather at the base of 

 rocks, or in overhanging ledges among heath, hardly ever 

 willingly sitting exposed on rocks. It begins to move about 

 midnight and may occasionally, on dry windy nights, be 

 found sitting at this time on rocks or stones preparing for 

 flight. It flies from about 1 a.m. till daylight, and has been 

 taken as late as 3*45 a.m., but is seen most freely on the 

 wing at 2 a.m. It flies most readily in dry weather, veiy 

 sparingly in gentle rain, not at all when the peak is en- 

 veloped in cloud, nor when the weather is very cold or the 

 wind especially high. It will not come to sugar, but is 

 attracted by a strong light and will dash up to and settle 

 upon it, but is difficult to net upon the wing, its flight being 

 very wild and swift. The female appears to fly but little. 

 One taken at night merely crawled about its hiding-place in 

 a deep hollow of a cairn of great stones and its movements 

 revealed its presence. We obtained one or two at rest on 

 the rocks by day ; others by netting at night. Throughout 

 our stay, every night, one of us worked the highest accessible 

 mountain peaks, while the other collected over the lower 

 slopes. This high mountain work is very severe ; the climb, 

 which when unencumbered is a pleasure, becomes toilsome in 

 the extreme when burdened with a weight of apparatus and 

 the clothing which is absolutely necessary. As soon as dark- 

 ness comes on the cold grows so intense that in spite of the 

 warmest wraps it taxes one's endurance to the utmost to last 

 out till the morning permits a descent. During all our stay 

 Mr. Kichardson had only one night and I not even one, 

 when there was not a gale of wind blowing at this elevation ; 

 often we were enveloped in clouds, when not an insect was 

 to be seen, and once I lost myself in a dense sea of mist, and 

 wandered about all night not knowing where I was till I 



