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sliglitly-prolected cells are those chosen by Chrysis lidcntata for her ovlpositloU 

 I once found satisfactory evidence of Chrysis bidcntata having burrowed through 

 half-an-inch of the clay stopping placed by the parent wasp. The parasite 

 was in the burrow covered with the dust brought down by her excavation to 

 form an entrance, a passage too small for the wasp to enter, but just large enough 

 for herself, and in the cell thus reached by her were to be seen her eggs freshly 

 deposited. 



On another occasion, a Chrysis bidentata alighted on a spot I was examining, 

 and where I had partially exposed some Bpinipcs cocoons, she commenced to care- 

 fully investigate them with herantennre and now and then scratch away some 

 earth partly covering them; she did not, however, 4eposit any egg. When a 

 cocoon contains eggs of bidentata there is often to be found at the uj)per end of 

 it a minute aperture through which the ovipositor of this CkVI/sis has been 

 thrust. At other times this aperture is wanting, simply because, as I believe to 

 have happened, the larva of sinnipes had not completed its cocoon wiifiQ the 

 Chrysis came to deposit her egga within it. One of the most remarkable points 

 in this history which I can neither understand nor explain, except it be anothef 

 instance amongst so many of the fecundity of nature which provides for 

 miscarriage through accidental injury, is that this Chrysis does aot deposit a single 

 egg only in the cocoon of odynerus, but actually drops in from six to ten of them. 

 These do not appear to he placed in any particular position, but simply faU 

 on the enclosed larva, and the excess in number may obviate the destruction 

 caused by the latter, especially when its movements are still active before the 

 completion of its spinning operations. In the instance above-noted, when I 

 found the Chrysis in the burrow of spinipes, the cocoon of the latter contained 

 five eggs in good condition. The wasp larva had ceased to spin, but had not yet 

 shrunk to those smaller dimensions which it rapidly assumes soon after. In 

 vaiious other instances I found two healthy eggs of bidentata, but often only 

 one, the shrivelled cases of from four to eight others being found with the 

 healthy eggs. I never found any evidence of the hatching of two eo'gs of bidentata 

 in the same cell, which, though it may seem a likely thing, would certainly be 

 an awkward circumstance. Chrysis bidentata remains longer than C, ignita in 

 the egg-state. Of a number of eggs reared by me most were hatched two days 

 after they were collected, but one remained three, and another did not hatch 

 until the fifth day ; and from the time of hatching the larvae were eleven days in 

 becoming full-fed. They changed their skins four times, at tolerably equal 

 intervals during their growth. The eggs of bidentata are 1.5 millimeters in 

 length, white, cylindrical, and very slightly arched, those of Spinipes are 

 larger, two or three milimeters in length, rather more arched, and of a yellow 

 colour. As doubtless the eggs of the two other Chrysides, neglecta and ignita, 

 closely resemble those of bidentata, the above description will serve to discri- 

 minate between them and those of the wasp should they be observed in the 

 nest of an Odynerus. The young larva of bidentata when hatched seizes that 

 of Odynerus with its claws and contrives to extract fluid nutriment from it with- 



