8008 



Insects. 



during the whole time she was on the eggs (and at one time as much as 20°), T think 

 there can he no doubt of iis being developed for hatching purposes. — E. W. H. 

 Holdsworth. 



Capture of Titniocampa leucographa at Lind field. — I captured two specimens of 

 Taeniocampa leucographa on the sallows, about a fortnight ago, in company with 

 other Taeniocampse, but have not been successful in meeting with more. — George 

 Stedman ; Lindjield, Sussex, April 7, 1802. 



Pupa are occasionally killed by Floods. — In the last number of the ' Zoologist' the 

 Rev. E. Horton asks whether "pupae are killed by floods?" There can, I think, be 

 no question that they are so occasionally ; that they are not, however, destroyed in this 

 way so frequently as, at first sight, might appear probable, long experience has con- 

 vinced me: led by a wonderful and almost unerring instinct, the larvae rarely descend 

 below the water-mark. I speak now of those which form their cocoons beneath the 

 moss or under the bark of trees bordering on streams, rivers, &c. Through my parish 

 runs a brook, each side of which is fringed with alder, poplar, ash, &c. : one day's 

 heavy rain is quite sufficient to swell this brook beyond its usual bed, and conse- 

 quently the lower part of the trunks of the trees is frequently submerged. When 

 this is the case a clear water-mark is left on the trees. This is a very bad locality 

 indeed for pupa-digging, but two rare insects, Cirraedia Xerampelina and Eupilbecia 

 innotata, both of which are ash-feeders, occur here, and accordingly I am diligent in 

 my search for the pupae : it is, I think, both a curious and an interesting fact that, in 

 no single instance, have I ever found one below the water-mark alluded to. It appears 

 to me evident that instinct warns them of their probable fate should they extend their 

 journey too far. It may here be objected that this theory can scarcely apply to those 

 insects which turn to pupae at the roots of, or under the earth about, such trees. The 

 objection is a plausible one, but twelve years' experience has taught me that pupae 

 will rarely be found at the roots of trees bordering streams which are ordinarily liable 

 to overflow their banks: the larvae, in this case, would seem to travel away from the 

 trees, and enter the pupa state elsewhere. Perhaps some observant pupa-digger may 

 be able to corroborate this statement. There will of course be seasons, as at present, 

 when the floods are so unusually high as to baffle the caterpillar instinct, and a 

 height or a place which, in ordinary years, would be quite safe, will then be sub- 

 merged. In this case I have no doubt whatever that the pupae are destroyed. 

 Mr. Horton considers that this question may have some bearing on the disputed 

 point as to whether pupae in confinement should, or should not, be damped. I a»ree 

 with him. At least it suggests the enquiry. In former years, as Mr. Horton 

 rightly observes, I felt doubtful on the subject, but later experience has con- 

 vinced me that, on the whole, it is better not to damp them. On the supposition 

 that, in their natural state, pupae require and have moisture, some collectors have 

 felt themselves bound to try and supply it, and, in doing so, have experienced much 

 difficulty in applying it in such a way as, on the one hand, not to give loo little, or, 

 on the other, too much. I am, however, most decidedly of opinion that this supposi- 

 tion is incorrect, and is not warranted by facts. In saying this I trust I shall not be 

 thought to speak arrogantly or dogmatically. There is one fact, which every skilled 

 pupa digger must have observed, viz. that in the vast majority of cases pupa- are 

 found on the northern or eastern sides of trees, i. e. the sides least exposed to rain. 



