Highland Insects. 127 



marvellous keenness of perception they are directed to their 

 unseen attraction we cannot divine. 



A permanent variety of the Oak-eggar moth (also easy to 

 catch in the way indicated above), or a species closely allied to 

 it (for it has been described as separate), is very common here 

 on the heather, over which its large chocolate-banded male may 

 be seen, winging his rapid flight in the hot sunshine in search 

 of his bride — who, larger still, and of lighter hue, reposes slug- 

 gishly near her birth-place. This insect must be dear to a 

 believer in the Darwinian theory, as it halts between the two 

 opinions of a species and variety ; its larva feeding on a dif- 

 ferent plant to that of the type form, and differing slightly, 

 and the perfect moth also differing slightly in colour, and 

 coming out at a different period of the year. 



Another fine moth, Petasia nubeculosa. first discovered 

 here as British, is found on the birch-trees, when the snow is 

 on the ground; for insects in Alpine situations seem less affected 

 than their southern brethren by climatic influences : as an 

 instance of this I may remark that I have seen Bomhus 

 lappomim flying and working here in the cold rain at five 

 o'clock in the morning. Concerning the Petasia, its original 

 captor adhered to the statement that he was materially aided 

 in finding the moths by certain tree-creepers, which flew from 

 birch to birch, chattering, and directing his attention to the 

 insects on the trunks. 



Parasitic upon some of these large moths must be a large 

 and handsomely banded species of Metopnus, one of the Ichneu- 

 monidce, which I took flying on Gray vel ; probably its larva is 

 nourished in that of the above-mentioned eggar (Lasiocampa 

 callunce), which would be sufficiently bulky to contain it. 

 Another very large and thin black species, allied to Pimpla, 

 with exceedingly long three-bladed ovipositor, was often ob- 

 served by me flying round the felled trunks at the woodman's 

 saw-pit, Dall; and it was most interesting to watch the prying- 

 ways of the creature, as it peered into holes and crannies, 

 delicately gauging the many galleries made by the larvaB of 

 Longicorn beetles, which its formidable weapon could scarcely 

 fail to reach. A small species of Spathius, supposed also to be 

 parasitic upon wood-beetles, used to occur plentifully in the 

 wood work of my solitary bed-dining-and-drawing-room, which 

 was riddled by Ptinus and Anobium, evidently its prey. The 

 Anobium (a genus to which the well-known " Death-watch " 

 belongs) kept me awake for some time by the frequency and 

 persistency of its ticking, clicking call, — one beetle answering 

 another by rapidly striking its hard maudibles against the 

 sides of its gallery, and the result being very clear and distinct 

 in the stillness of the night. 



