FOREST SHELL-WASP 409 



in the center, fading to a transparent white at either end. 

 The yellow center is in reality the young wasp, and the trans- 

 parent end the extremities of the film-like egg-shell. The 

 eggs are laid one at a time, that is to say, the wasp deposits 

 in one cell, waits for it to hatch, then provides the young with 

 sufficient food to bring it to maturity and plugs the cell with 

 moss before laying the second egg. 



Its chosen prey is doubtless small caterpillars, for I 

 found three uneaten heads in a cell containing a full-grown 

 larva. The egg is attached to the roof of the cell by its pos- 

 terior end near the back, and hangs downward. Thus the 

 young wasp hatches with its head in mid-air. 



The mother wasp guards her cells closely during the 

 period of incubation, often resting within the cell containing 

 the new laid egg. She crawls to the entrance on the roof 

 of the nest, then turning round, backs in, clinging to the un- 

 derside of the roof. Her head peering out, with its antennae 

 waving here and there, adds to the illusion of the nest being 

 the shell of a snail. 



The two nests on which this life history is based were 

 found on May 14, in the deep forest. One of them I lost, 

 but let us go back to that day and the remaining nest. If I 

 leave it upon its swaying air root for further observation, I 

 will probably never find it again. It blends perfectly with 

 the emerald surroundings, a tiny object in a part of the for- 

 est that I have visited but once. Therefore I will carry it 

 home to the laboratory just as it is, and put myself in diffi- 

 culties at once. 



The first cell contains a full-grown larva and the second 

 is empty, save for a single, freshly deposited egg. The lar- 

 va is quite satisfactory. It has finished its meal of cater- 

 pillars and will soon pupate, giving me much desirable in- 

 formation and no trouble. But what of the egg? If, true 

 to the rule which is usual among solitary wasps, it will be- 

 come a hungry living grub in forty-eight hours, how then 

 shall I feed it? I have not given the parent wasp a chance 



