NOTES ON COLLECTING, ETC. 91 



probably Sesi'a bembeciformis may sometimes remain two years in either 

 the larval or pupal condition. — F. J. Buckell, Canonbury Square, N. 

 March, 1891. 



Referring to Dr. Buckell's statement as to the duration of the larval 

 state of Cossus lig?iiperda, etc., I think there can be but little doubt 

 that woodboring larvae live two, if nor three, years in that state. I 

 believe there is little question that this is the case with C. ligniperda 

 and Sesia sphegiformis and possibly also with Zeuzera cesciili, S. cynipi- 

 formis, S. apifonnis, etc., although I am rather inclined to the idea 

 that the three last mentioned pass two years as larvae. I never heard 

 of any one breeding any of these species from the egg, so one can 

 only argue from finding larva of two or three very distinct sizes in the 

 burrows at the same time of year. — C. Fenn, Lee. April, 1891. 



Cossus LIGNIPERDA.— In August, 1890, I found, crawling on a road, 

 a nearly full-fed larva of this moth, which I captured and fed on elm 

 wood. On the loth of May last, I was pleased to see it had gone 

 into pupa. It could only just have turned, as it was quite soft and of 

 a light brown colour. It soon got harder and darker, and to-day, to 

 my surprise, I found a lovely male specimen emerged. Is not this an 

 exceptionally short time for it to remain in the pupa state ? I thought 

 it always remained for a year or two. I might mention that I kept the 

 larva in an ordinary wooden breeding cage, with glass front, and gauze 

 at the top and sides, and it never attempted to gnaw its way out. 

 Is not this also exceptional? — W. P. Blackburne-Maze, Boundes 

 Park, near Tunbridge Wells. May 25///, 1891. [When the larva of 

 C. ligniperda is full-fed it makes an autumn cocoon to hybernate in. 

 In the spring it generally leaves this cocoon, and without feeding, spins 

 another in which it pupates, the moth emerging the following June 

 or July. I have known a larva to pupate in the cocoon it hybernated 

 in, but I do not think that it often does so. I have never before 

 heard of the species not remaining in the pupal stage at least five or 

 six weeks, nor have I heard of the pupal stage extending to more than 

 eight or ten weeks, although the larva is two or three years coming 

 to maturity. — Ed.] 



Times of Emergence. — I can only speak from memory on this 

 point. I have found Nyssia zotiaria drying their wings at 10 a.m. and 

 at 4 p.m., and more than one at each time. They may possibly 

 emerge at all times between, but I have not noticed. Zygcena 

 filipendida. seems to emerge from 10.30 to 12 a.m. Sesia bembeci- 

 formis emerges here from 7 to 8 a.m., Smerinthus populi, 6 p.m. I 

 bred a lot of Vanessa cardui some years ago, in a room facing the 

 west, and hot in the afternoon ; these emerged from 2 to 4 p.m. 

 The effect of an east wind is very noticeable, even on pupce forcing 

 on my kitchen chimney-piece. As soon as the wind changes to the 

 east they stop, and wait till it goes round again. — Geo. A. Harker. 

 April, 1 89 1. 



On the broad lines I have stated (vol, ii., p. 70; insects emerge from 

 the pupa with a certain regard to their times of flight, — a provision 

 of nature, and one that will account for the fact that so very few 

 captured females are infertile. By this explanation the emergence 

 of butterflies, day-flying Sphinges like the Sesiidce, etc., would naturally 

 take place in the morning ; and the rest some time either in the 



