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THE ENTOMOLOGIST S RECOED. 



and the next necessity for enlargement is met by an abandonment of 

 the curved case, and the building of a new one, quite cylindrical in 

 general form, from pieces of the leaf the larva has mined. Of the 

 making of this case Mr. Sich has given an admirable description in his 

 " Notes on the genus Coleophora " {Proi-. Sth. Lond. Ent. ayid N. II. Soc, 

 1904, p. 8), so that, as it is unnecessary that I should describe it again, 

 I shall confine myself to adding a few notes upon points Avhich he did 

 not mention in his account. Of the four larvae I possessed, the first 

 one, on May 6th, fixed its case below the margin of a leaf and 

 commenced to mine. Between this date and May 11th, an unusually 

 large mine was made between the cuticles, and the larva was 

 frequently wholly out of the old curved case. Towards the end of this 

 period, the portion of the leaf intended by the larva to be used as a 

 case, semi-transparent at first, was gradually darkened, presumably by 

 the deposition of a larval secretion, as the larva itself could readily be 

 seen through the surrounding lighter area, when the leaf was held up 

 to the light. It may be, however, that the cuticle was darkened by the 

 deposition of a dark silken substance spun by the larva. It was 

 certainly remarkable that only just that part required for the 

 construction of the new case was darkened, the rest of the mined 

 portion retaining the ordinary dead brown tint of the dried cuticle. 

 By May 12th, the new case was completed and nearly severed from 

 the leaf. For a short time, a few hours after the new case was 

 separated, the old curved discarded case remained loosely attached to 

 one of the anal valves, but it soon fell oft'. Another larva began to 

 form its final case on the 14th, and, in that particular instance, the 

 new house was not quite straight, but followed the curvature of the 

 edge of the leaf, because the larva used the edge for one of its sutures, 

 and thus saved the making of a second seam. This is the only 

 curved final case I have seen. Mr. Sich informed me on May 11th, 

 that, in nature, most of the larvae were then assuming the straight 

 cases. It must be noted that these cases are final, and are never 

 enlarged. We may compare them with the cocoons, which most larvae 

 make before the final change, as places of complete safety, Avhere they 

 may undergo their final metamorphosis. It would be more or less 

 inconvenient for the Coleophorid larva to change to pupa in a curved 

 case such as in this species, so that the change of plan in the case is 

 almost imperative. Of course we must note this difference in the 

 comparison, that the larvae of most cocoon-making species do not feed 

 after they have built their chambers, whereas the Coleophorid does so. 

 On one occasion a larva was seen walking about with its new case, 

 which it had just detached, of which neither end was yet finished to 

 any definite form, nor was the usual depth of colour attained, and the 

 substance of the case was soft and flabby. The case was flattened and 

 far from cylindrical, and did not assume its proper shape, colour and 

 finish for several days, but it was most unusual for a case to be cut 

 out before it had become very deeply coloured. In another instance, 

 the old curved case was firmly attached about f along the side of the 

 piece of leaf taken for the new case. Thus there was a hole in the side 

 of the linear case which had to be stopped up. I did not see this 

 interesting little undertaking carried out, but can only give the result. 

 In the completed case, the place of the hole in the side was very 

 plainly visible as a depression, lighter in colour and more transparent. 



