140 THE entomologist's record. 



empty cocoons of different dates that have come under my inspection. 

 One seldom approaches an aspen or Lombardy poplar, still less a group 

 of such trees, without finding empty cocoons. Here, too, the wandering 

 propensity is observable, one cocoon being noticed on the bark of an 

 oak ten yards distant. More often, however, one would suppose that 

 the innumerable crevices of an old poplar trunk offer sufficient induce- 

 ment for it to remain, and I am bound to say that it manages only too 

 successfully to evade the most diligent search. My net result is but 

 three living pupae, though I have carefully scrutinised hundreds of 

 trees, and two of these were spun up on the underside of bark near the 

 root, prized off with a trowel. Such a position, no matter on what 

 point of the compass, is the one most often selected by the larva if it 

 be available. I have noticed, however, that the prolonged humidity of 

 winter often kills them in this situation. The cocoons also occur on 

 any part of the tree, generally within six or eight feet from the ground, 

 and I believe that I am not exaggerating when I say that I have 

 recently discovered scores of fresh ones that have been ripped open 

 from end to end by birds, the cast-off larval skins still lying at the 

 bottom. I conclude that this is mainly the work of tits, as one 

 cocoon, under loose bark at the root of an aspen, which had been thus 

 treated, could only have been reached by a small bird. With this 

 wholesale plunder the species is undoubtedly decimated and kept down 

 to a very large extent, and one wonders how many actually survive. 

 Though birds' eyes may be sharper than mine, I am proud enough to 

 believe that a fair proportion of these would have fallen to my lot had 

 I forestalled the feathered foe by searching in October rather than 

 March. [Moral : Don't put off till the spring what can be done in 

 the autumn.] 



('crura bictifipis. — The climax of one's interest has of course been 

 reached in the successful quest for this species. In the Norfolk list it is 

 recorded forMerton, Sparham, and Aylsham, and a larva was taken at 

 Cromer in 1902 {ride Ent. Record, vol. xv., 53), but I was able to satisfy 

 myself that the species occurred closer to Norwich by finding, in the 

 autumn of 1901, three old cocoons on birch-trunks at Stratton Straw- 

 less, some seven miles from the city. I had failed, however, to follow 

 up this clue until the present spring, when, with a return of the 

 season's ardour, I determined to prosecute a vigorous and thorough 

 search. I began by reading up every scrap of information respecting 

 the species from books old and new, and from the monthly periodicals 

 for the past sixteen years, and I should like here to express my thanks 

 both to Mr. Tutt for his " Practical Hints," and also to Dr. Chapman 

 for his valuable article on the species in Herefordshire {vide Knt. 

 Record, vol. vii., p. 73). In fact, it is the strong corroborative evidence 

 that I can bear to his experiences in my own, and the practical value 

 that I attach to the placing on record of simple facts and observations, 

 that has induced me to write this article as a supplement to his. I 

 rode over to Stratton on March 18th, and was remarkably fortunate in 

 at once discovering a new locality, taking in three sub-districts as 

 many as sixteen cocoons m the space of five hours. They were all on 

 birch, and about half-a-dozen were merely fragments of ancient date. 

 It would be difficult to say how old they were, but certainly they had 

 weathered more than two years. Several of the remainder, by the 

 comparative freshness of their lining and pupa shells, I estimated as 



