OF PAPILIONACEOUS INSECTS. 55 
We now proceed to give an account of the sub- 
stance of the eggs of Lepidopterous Insects. These, 
like those of birds, consist, first, of a coat or shell, 
which is strong, flexible, and much of the consistence 
of honey. It will not easily yield to the knife. It 
contains little calcareous matter, if any at all, and 
consequently resists the action of the muriatic and 
other acids. 
With the composition of the fluid, which is 
contained in these minute shells, we are not at all 
acquainted, and can only suppose that it is analogous 
to the white and yolk of birds’ eggs. When the 
egg has arrived nearly to the time of hatching, the 
embryo may be distinctly seen by the use ofa strong 
microscope. It is coiled up in an annular form, as 
in the following figure of the egg of a Priest-hawk 
Moth, (Sphina Ligustri.) 
Y) 
Some of the eggs of this order of insects are 
covered with hair, or a downy substance, as may 
be instanced in those of the Figure-of-eight Moth 
(Bombyx cceruleocephala.) 
There is considerable variation in the number of 
eggs laid by different species. The Silkworm Moth, 
(Phalena mori,) lays five hundred ; the Great Goat 
Moth, (Cossus ligniperda,) one thousand ; and the 
Tiger Moth, (Callmorpha Caja,) one thousand six 
