2222 Insects. 



numerous depots of eggs similarly situated, without any presiding guardian exercising 

 over them a special care. Shortly afterwards I surprised another female of the same 

 species in the act of oviposition. She had already laid two eggs side "by side, and was 

 about to deposit the third, which she did between the tips of the two others, so that 

 the three formed a triangle ; then, after walking over them twice or thrice, she fastened 

 down another in the place best suited for it, and proceeded in a similar manner till 

 she had laid three others. She scarcely ever made use of the antennae or palpi to as- 

 certain the proper situation for the forthcoming ovum ; but by probing with the apex 

 of the abdomen she accomplished all she desired. After completing the final number 

 of eggs, she continued brooding, as it were, for a short time ; no doubt being engaged 

 in ascertaining if she had produced the requisite number. This done, she all at once 

 became animated with a new object, carried out by a new mode of procedure. Hasten- 

 ing with great rapidity, now to one side and now to another, now retracing her steps 

 and now wheeling all round, and at the end of every turn placing her mouth against 

 the leaf, accompanying this action with a rapid movement of her head, two or three 

 times repeated ; she seemed to be engaged in a rural dance to celebrate her late happy 

 delivery. It was some time before I could trace the nature of the new operation, 

 till, turning up the leaf to the light, I observed a series of extremely delicate threads 

 already spread over the eggs in various directions. She was now engaged in spinning 

 her web, if I may use the expression ; and those rapid movements of the head, when 

 brought into contact with the leaf, were to fix the rapidly-produced threads; while her 

 crossings and counterwindings gave direction to the warp and weft that would enve- 

 lope her future progeny. I watched her about half an hour, and I left her in full ac- 

 tivity, which she never had remitted from the time she commenced. The eggs are 

 usually placed in the hollow between the nervures of the leaf, and occur on the upper 

 as well as on the under surfaces of leaves, though most frequently on the latter. 

 When the web is completed, they appear in white sub-oval glazed patches, not unlike, 

 at a short distance off, the scale of a fish, apparently continuous with the substance of 

 the leaf. The eggs are oblong-ovate, minute, white. I have found the number va- 

 riously, five, seven, eight, sixteen. Two other species frequent the oak in the woods 

 here, Psocus ochropterus, Steph., and P. longicornis, Fab., but I have not yet obtained 

 an acquaintance with their economy. They are all cowardly, timid creatures, betaking 

 themselves to the other side of the leaf when disturbed. Huber is of opinion that 

 they feed upon the Uredines of plants, which he supposes have a tendency to follow in 

 the wake of the Aphides. I have made no observation to this effect. I once obtained 

 a great number of a small, hyaline, iridescent-winged species, which I did not ascer- 

 tain at the time, from Usnea hirta (a kind of lichen, gathered from the trunk of the 

 birch), which I had placed between the leaves of a book to fit it for the herbarium. 

 They appear to have lived upon it, as I found them after an interval of some months. 

 What confirms this is, that the lichened trunks of trees, and the surface of stone walls 

 similarly invested, are the favourite resort for numerous larvae. — James Hardy ; Pen- 

 manshiel, by Cockburnspath, Berwickshire, July 10, 1848. 



On killing Insects by Heated Air. — Perceiving, by the correspondence of some of 

 the contributors to the ' Zoologist,' that chloroform and prussic acid are both used to 

 take the life of insects, and thinking it not improbable that the use of either may be 

 inconvenient to many entomologists, I send you the following account of the means I 

 have used for years. Having a tin box, six inches by four and two in depth, with a 

 piece of cork at the bottom (fastened by a rivet at each corner), to which the insect is 



