INSECT LIFE 181 



The wall argus is a constant sunner ; and it suns 

 more often on the bare ground or short turf than on 

 a seat aloft. But, though it is so fond of burnt, 

 flowerless, and trodden spots, I find it on the heights 

 by the sea near Alum Bay, where the air is steeped in 

 scent, and the ground one grand purple with the 

 heather ; and it is a nectar - drinker. On these 

 glorious heights I have seen the two or three 

 common white butterflies flying in quite a fresh 

 breeze, and am impressed by the progress they can 

 make against the wind. They appear to do it by 

 tacking across the wind, but even this is no mean 

 success, considering the flimsy paper look of their 

 wings. The whites, like the meadow-brown class of 

 fliers, have wings that look as if they must be con- 

 trolled by the air ; whereas many insects some hawk 

 moths, for example have wings cut and strongly 

 nerved to control the air. Midway between those 

 that look air- controlled and those that look air-con- 

 trolling comes this wall argus, with the grayling and 

 the marbled-white. But there are a number of 

 smaller butterflies, the fast little blues and brown 

 arguses and coppers, that it is not easy to fit into 

 either class. A common blue's wing in cut and text- 

 ure looks somewhat as if it would have no driving 

 power as if it would only be of use for bobbing and 

 fluttering after the style of a meadow- brown butterfly. 

 Yet the common blue is a quick and nimble little 

 flier. It seems to progress by tack and zigzag; has 



