234 NATURAL HISTORY OF WASPS, 
colours are quite distinctly developed in the perma- 
nent integument. 
At this earlier period all the lineaments of the 
future insect are perfectly to be traced, but the 
limbs look thick and clumsy. With a little care and 
patience we may withdraw large portions of the 
covering which gives the limbs this appearance ; and 
the glove, so to call it, bears the exact impression of 
all the parts beneath. The eyes of the future wasp, 
the jaws, the antenne, everything indeed, bemg as 
faithfully represented in its cast skin as the eyes 
and each scale of a snake are in its slough. 
For the complete examination of the lining of a 
cell we must choose one which has not yet been 
opened, where the round white cap still rises high 
above the level of the cells, uninjured. By soaking 
in warm water the cocoon may be drawn out as a 
long bag, open at the farther end, which, ‘when 
washed and blown out, and dried, retains the form 
of the cell. To the unassisted eye it looks like a 
film of collodion, or goldbeater’s skin; but the mi- 
croscope shows it to be made of threads which have 
been laid down separately in a wet state, and have 
run into each other. Its structure is uniform through- 
out, only it is thicker at the cap end than elsewhere. 
Cells, where the larva has not yet cast its first skin, 
like virgin honey-cells, have no lining membrane. 
The empty cell can scarcely be said to be quite at 
liberty as yet; it has to serve another purpose before 
it is prepared for the next tenant; for the new-born 
insect often re-enters it, or an adjoining cell, to rest 
awhile after her exertions. But it is the tail now, 
