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out of the body of the caterpillar when it was evidently 

 full-fed, and just before assuming the pupa state ; both 

 caterpillars were fixed to the same leaf of beech by a single 

 silken cord or web round the body, as though they were on 

 the point of changing to pupa, when overtaken by death 

 caused by their relentless little foes. These larvae at once 

 attached themselves to the same leaf by a glutinous secretion 

 of a pale brown colour, as in the species of Eulophiis observed 

 by Geoffroy {^History of Insects, vol. ii.), and to which 

 family I think it very possible our little friends belong. They 

 did not all emerge at the same time, the larvae from Demas 

 coryli, although amounting to only 17 in number, extended 

 over a period of five days, and were of a semi-pellucid white, 

 up to the time of changing to pupa, which took place in a 

 few hours, they were then of a jet black colour ; the larvae 

 from L. camelina being of a pale watery green colour on 

 emerging, but as quickly changing to black ; the pupae 

 appearing very wrinkled, and lying on their backs, with limbs 

 showing very prominently, particularly the antennae and legs, 

 although apparently soldered tightly to the breast. According 

 to Westwood, the majority of these insects pass the inactive 

 period of their existence naked, and not enclosed in a cocoon, 

 as do many other species of Ichneumonidse, such as Micro- 

 gaster glomeratus. In a state of nature these pupa most pro- 

 bably drop to the earth to undergo their final metamorphosis, 

 as the least shake will disturb them, leaving the cast-off skin 

 firmly attached to the leaf, secured by the gummy secretion. 

 They also evidently eject small nodules of frass just before 

 the change takes place, as there are several little clusters 

 immediately round them. I know with what a large amount 

 of prejudice many of my Lepidopterist friends look upon 

 these parasites, as being almost as inveterate enemies to 

 themselves as to the poor caterpillar. Mr. Westwood, in his 

 Modern Classification of Insects, says that these insects are of 

 vast importance in the economy of nature, by preventing the 

 too great increase of different species of insects, especially of 

 the caterpillars of butterflies and moths, of which they destroy 

 a great number; it having been observed that a super- 

 abundance of any species of insects is attended with an 

 increased production of its parasitic enemies. Perhaps it may 

 be some slight consolation to my Lepidopterist friends, to 

 know that, although their choice rarities are sometimes 

 destroyed by these insect pests, they are not alone, for the 

 Coleopterist's, as well as the Hymenopterist's and Hemipterist's 

 specialities, are all liable to the same attacks, although perhaps 



