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mass of silk. A cocoon case measures a little over an inch 
long, so we can judge the perfect moth to be about the size 
of the British “Oak Egger moth,” Lasiocampa Quercus, 
with wings stretching about 2J inches. I have searched in 
vain for a pupa sound enough to dissect ; they are all dried 
up and shrivelled within the unbursted cocoons. The outer 
fibres of the silk adhere fiimly to the interior of the nest, 
and mixed with the silk near the end are numbers of eggs 
of the moth, proving that some of the cocoons had burst and 
the moth escaped. 
The nest has small openings at each extremity for the 
escape of the moth, and the hole where it is attached to the 
bough. 
I cannot detect any evidence about the nests which would 
lead us to think that they are formed gradually piece by 
piece over any length of time like the nests of wasps, bees, 
and ants. On the other hand, they are evidently begun and 
completed in a short time, when the larvae are approaching 
their full growth, when instinct impels a number of them to 
band together and rapidly construct a common shelter and 
retreat in which to await the strange dormant stage of their 
existence. 
They must proceed to masticate and make a vegetable 
pulp in sufficient quantity to form the covering to their 
common nest, and be able to decide its capacity to hold their 
whole number. The strong leaves must be applied whilst 
the pulp is yet soft and sticky, and the outside completed 
before a retreat is made to the interior— then the larvae 
must emit each length of the silken thread, and fill the nest 
to the full ; and lastly, each larva must take up its proper 
rank, spin for itself a delicate cerecloth around its changing 
form, and entomb itself to wait the final change which 
gives it a renewed and almost seraphic life ; truly it is a 
marvellous episode in the life of a gregarious caterpillar. 
