LASIOCAMPA. 41 



Tortricids, Cossus, &c, an awl-like effect probably occurs, but in all 

 cases of lids, as for instance in Sesiids, the process is probably the 

 same as that which occurs in Cochlidion limacodes. Most people are, 



1 think, familiar with the effect of a very localised interference being 

 per se harmless, but determining at once that a strain should pro- 

 duce powerful effects." 



The males of L. quercus show in a most marked degree the 

 phenomenon known as " assembling." Mathew notes the $ s coming 

 up to a newly-emerged $ at Barnstaple 6 or 7 at a time, and 

 Blaber records 22 males attracted by a $ , August 1st, 1887, at 

 Crowborough Beacon, the box containing the 2 being placed on a 

 gorse bush. The attractive odour of the ? is very persistent, and 

 lasts for several days. Williams notes it (Ent. Pec, x., p. 106) as 

 lasting from July nth — 20th; Mousley observed a large number of 

 S s attracted by a small piece of $ abdomen, which was impaled 

 on a thorn in a hedge, the $ s crawling up the stem on which it 

 was placed until they reached it, when they flew away. Vicary 

 records that in 1875, at Newton Abbot, a male was seen hovering 

 over a pupa, which later produced a 2 moth ; Robinson notes a 



2 that attracted several males after it was dead ; and Arkle observes 

 that Murray placed 3 $ s in a perforated zinc case on July 19th, 1894, 

 when only 2 males were attracted, owing to its being late, 5 p.m., on 

 Witherslack Moss ; the £ was removed on the 20th, when the 

 satchel was taken to the Isle of Man on a collecting expedition till 

 the 23rd; Witherslack was visited again on the 24th, and though no 

 other $ had been in the satchel since the 20th, numbers of $ s were 

 attracted to it and crawled inside; on the 26th others were attracted 

 at Clougha Pike, and "troops" on the 27th at Witherslack, and on 

 the 29th two at Halton Moss. So much for an empty satchel ! On 

 the other hand, Doubleday insists that a virgin $ of L. querciis 

 seldom lives a week, and generally ceases to be attractive to the 

 males after 3 or 4 days. Hamm observes (E. M. M., xxxi., p. 74) 

 that, on July 7th, 1894, he had a ? , took it out, but failed to 

 attract a single $ , although the weather was apparently everything 

 that could be desired; yet, on the 15th, the bag in which he had 

 carried the female, 8 days previously, was a great source of attraction 

 to many males, which must have been drawn by an odour that 

 had been transmitted to the bag by the female when she was carried 

 therein. Zeller records (Isis, 1847, p. 422) that he had a $ L. var. 

 spartii (=sicu/a), which he killed and set, and that two months after- 

 wards a S Pachygastria trifolii was attracted to the trunk in which the 



? was contained. He refused to consider it a mere coincidence, in 

 spite of his firm belief that P. trifolii and L. quercus var. spartii were 

 quite distinct species. We have already noted (anted, p. 3) the 

 rearing of a hybrid between these species. That the sense by 

 means of which the males detect the females resides in the antennae 

 appears to be certain. 



The imagines of L. querciis are much less frequently taken at light 

 than are those of some of the allied species — Eutrichids, &c. — yet Dewey 

 records it as coming in abundance one night in July to the electric light 

 at Eastbourne (although the sex is not mentioned). Jones captured 

 females at light at Eltham on August 14th, 1866, and July 9th, 1874, 

 and Christy one at Wicken, July 20th, 1890. 



