WAYS AND HABITS OF CATERPILLARS. 
By Harotp W. B. Moors. 
Very varied and interesting, and, in some instances, curious and puzzling, are 
the habits or actions of caterpillars, What, for example, can be more curious 
than the habit some have of devouring the egg-shell soon after they have 
hatched. This habit exists among many caterpillars, both of butterflies and 
of moths. The caterpillars of our common yellow butterfly Callidryas 
eubule, and of our black and red butterfly Heliconius melpomene, act thus, and 
so do those of the hawk-moth Anceryx caicus, and of the grass-moths 
Laphygma frugiperda and Lycophotia infecta, to mention but a few instances 
of this habit that have come under my observation. One would imagine 
that almost the first thing the caterpillars would do after hatching would be 
to look for the tenderest part of the food-plant, and there begin feeding, but they 
begin by tackling their egg-shell. Of course, the shell is not hard and tough, 
but very brittle, so that they have no difficulty in disposing of it in the manner 
specified. In explanation of this action where it occurs, it has been sug- 
gested that it is done by the caterpillars to remove one of the signs of their 
presence, and that it is thus protective, serving to throw parasites and other 
enemies off the scent, so to speak. It has also been suggested that they eat the 
egg-shell as being the most easily edible matter nearest to hand. 
Another equally curious habit possessed by some caterpillars is that of 
devouring their cast skin at the different stages of their growth. Of this there 
have come under my notice some good examples, from which I select the two 
following :—I once had some sociable caterpillars, about two dozen, feeding 
on the leaves of Smilax, a wild vine. They were those of a moth, which has not 
been identified, and were not full grown when I got them. They all cast their 
skin at the same time, the sloughed skins adhering to the leaves. As soon as 
its new cuticle had hardened somewhat, each caterpillar set to work devouring 
the cast skins, save the horny shell of the head, nor did each confine itself to 
its own skin, but fell to upon the first skin encountered, whether its own or 
that of a companion. The other example refers to the caterpillar of the 
Passiflora butterfly Heliconius melpomene. The cast skin, as is the case 
with the moth just mentioned, adheres to the leaf of the food-plant, and is 
devoured by the caterpillar, spines and all, the horny shell of the head being 
the only part rejected. 
With certain caterpillars the cast skin does not adhere to the leaf, but is shed 
in such a@ way as to fall, and among such it cannot therefore be eaten. I 
do not know, however, whether among those that cast the skin in such a manner 
that it remains adhering to the leaf, it is a more or less general habit to eat the 
cast skin. Ai least, all which I have observed to shed the skin in this manner 
have always eaten it shortly afterwards, and before resuming the attack on 
the leaves of their food-plant. More extended observation will be necessary 
to decide the point. 
