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Beauty) NV. héspidaria, This was the more remarkable because in this 
family. there were only three other species, Biston hirtaria, Amphydasis 
prodromaria, and A. betularia, in all of which, strange to say, the 
females had a larger expanse of wing than the males. 
There was one more group of moths, in which the females were 
more degraded than any of the examples already given ; in fact, it had 
been remarked of them that they were simply egg sacs, while the 
males were pretty lively moths. There had curiously been 
much difference of opinion as to what group of moths they should be 
classed with, some at one time leaving them with the Bombycide, and 
others with the Zzmee@. They were known by the name of the 
Psychide, and were remarkable from the habits of the caterpillars, 
which formed for themselves a case, somewhat similar to that con- 
structed by the caddis-worm, composed of pieces of bark, leaf, or 
some similar material, fastened together by a kind of glue or silken 
substance secreted by the caterpillars. When engaged in eating, they 
protruded a portion of the fore part of the body from the case, and, as 
they increased in size, enlarged the case by first slitting it, and then 
letting it out by the addition of more material. Before moulting or 
changing to a chrysalis, the mouth of the case was closed, and in the 
latter state it served the purpose of a cocoon. When the final change 
took place the male escaped, but the female of one, Fumea gemella, 
crawled out, in appearance like a little worm, and, after depositing he, 
eggs in the case, died. Others, like Psyche gramined/a, if females, did 
not emerge from the case, but deposited their eggs within, died, and 
shrivelled up. The young larvee commenced their experience of life 
by eating up their dead mother’s body, as rank a case of cannibalism 
as one could wish for, being, to say the least, an unnatural proceeding. 
Some of the female Psychidze were not only wingless, but almost 
footless, without azéenia@, and had eyes without facets. 
Two or three questions naturally arose as to why the females should 
be so different from the males? Was there any perceptible difference 
in the caterpillars to account for the difference in the moth? Were 
there analagous cases among other insects ? 
To the first question no satisfactory answer could, at present, be 
given. Those who had experimented upon moths and butterflies knew 
that alternations of scanty and bountiful food, or keeping them on 
scanty food only, tended to produce dwarfs and montrosities, and that 
keeping chrysalides rather dry or exposing escaping moths and butter- 
flies to the action of dry heat, prevented the unfolding of the wings. 
These things, however, took place with males and females alike, and 
