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out apparently making any aperture in the skin until it approaches to mature 

 growth itself. I have very carefully examined a spinipes larva that waa thus half 

 sucked away, I cannot say eaten, and I could find no mark at the spot whence I 

 had just removed a Chrysis larva. I have several times squeezed the spinipes 

 larva firmly without any fluid exuding except one out of several trials, in which 

 I squeezed the larva almost to bursting, when a drop of clear fluid exuded. 

 Nor is the Chrysis larva particular as to where it seizes the Odynerus, any point 

 that may offer itself to its jaws being attacked. "When the devourer is nearly 

 full grown and the victim has beccome very flaccid, a process that may be 

 called eating takes place, and the spinipes larva almost entirely disappears. 

 The manner in which Chrysis neglecta, C. ignita, and spinipes itself eat the 

 little green sawfly grubs is precisely similar; that is the larva of each when 

 consuming its prey takes one grub after another, at first sucking the juices 

 through the skin, and when further advanced in growth returning to devour 

 them skins and all, the heads alone, which are homy in texture, being rejected. 

 I have already remarked that Chrysis bidentata casts its skin four times. 

 It does Bo at tolerably regular intervals of two days or rather less. I have 

 twice seen this process in operation, when the skin splits down the back of the 

 anterior segment and the corneous covering of the head splits into two lateral 

 halves, which remain attached to the skins when the shedding is completed. 

 As compared with the larv.-e of Lepidoptera and of Coleoptera, they feed up 

 so rapidly that one marvels how they have time to change their skins so 

 often, many a Lepidopteron requiring four or five days for the process of 

 once changing its skin, while Chrysis ignita is fed up in six days, during 

 which it has found time to change its skin four times. "What astonished me 

 much was the great similarity between the larva of a Chrysis and that of an 

 Odynerus, a similarity that I believe to be a true and not merely a superficial 

 one. Thro«ghout its existence the larva of spinipes is yellow, its viscera are 

 tolerably visible through the integument, especially portions of a yellow tor- 

 tuous duct in the lateral dorsal region from the fifth segment backwards. 

 In Chrysis the larva is white, and its interior is more masked by masses of 

 white fat. The first spiracles, which properly belong in most larvae to the 

 third segment, are in Chrysis bidentata at the anterior margin of that seg- 

 ment, but in Odynertis spinipes are actually in the second segment. The 

 form of the head and the parts of the mouth are very similar in both. This 

 resemblance of the two larvse is closer than that between the larva of spinipes 

 and of the common wasp (Vespa vulgarisj, and curiously enough, in those 

 points in which the larva of Chrysis least resembles that of spinipes — as 

 form of jaw, distinctness of viscera as seen through the skin, and colour — 

 it more nearly resembles the larva of Vespa vulgaris than that of spinipes. 

 Like the larva of spinipes, and other hybernating Hymenoptera, that 

 of Chrysis shrivels to a certain extent after it has spun its cocoon, the 

 skin becomes loose and thrown into very fine folds, the head is bent down 

 on to the front of the body, and the lateral and subdorsal prominences 



