THE SUBSTITUTE. 
211 
pies to all uninvited guests. On 
the twenty-fourth day a great 
number had got into the third 
moult ; one poor fellow was look- 
ing poorly, saw him fall from the 
spray ; I lifted him up, he held on 
a little with his pro-legs, then 
reeled over and fell again ; no- 
ticed a contraction at the sides as 
if drawn in by spasms, then a vo- 
miting and purging ensued, and 
the body of a blackish colour 
(likened the symptoms to cholera), 
and the poor fellow was reduced 
to half his normal size, and at last 
I found him a blackened corpse. 
I tried to find out the cause, (as a 
great number had died in the 
same way, and I was fearful that 
I should lose them all), but with- 
out efifect until some clays after, 
and I attribute it to the following. 
In changing the food I threw the 
skins of some of them away, and 
then I recollected that after 
emerging from the old skin they 
invariably ate them, as I had often 
seen them do, and merely thought 
they were not choice in their se- 
lection, but alas ! it was not so, as 
I found out to my cost, and that 
the cannibal propensity they ma- 
nifested was requisite for the crea- 
tures well-doing, and was part of 
the economy of insect life (or 
rather of pusses’): noticed some 
others unwell, and symptomatic of 
a like termination, a contraction 
in the region of the stomach with 
vomiting and purging, and at last 
death put an end to their suffer- 
ings: resolved to make some ex- 
periments to test the validity of the 
theory 1 bad formed. I placed six 
of them in separate boxes before 
casting their skins for the last time, 
three of which I took away as 
soon as they had moulted ; they 
seemed uneasy, and evidently in 
search of something, as they 
crawled about the leaf; saw the 
three which were left to them- 
selves eat their old jackets, and 
theu rest for some hours ; they in- 
variably began with the tail 
sheath, and ate all but the head- 
case ; that they rubbed off in the 
manner birds clean their bills: 
they all began to eat and looked 
well for some time, until nearly 
full grown. I then noticed two of 
the first three looking dingy, the 
muscular contractions, &c., en- 
sued, and then they died. The 
second three and the last of the 
others, however, did not manifest 
any signs of illness, but some days 
after I observed them all four 
looking different, the colours alter- 
ing, and felt afraid that I was 
going to lose them all, as they re- 
fused to eat, but more active than 
I had seen others that were struck ; 
I was pleased, however, to see that 
they had only been looking out 
for an eligible site whereon to 
construct their winter habitation, 
as they all four began to spin, and 
very active they were when the 
sun was shining on them, (and, 
by the way, with what vigour they 
eat under the same circumstances, 
puss larva, and all others that I 
have kept, three bites to one as 
compared with what they do in 
the shade), fabricating their oval 
cocoons, and before night they 
were hid from view, but I could 
see they were busy upholstering, 
and heard them nibbling the box 
like mice, and covering the roof 
with the particles, all but one spot 
about an inch and a half in dia- 
meter, which was left clear like 
horn, (and which is softened by 
the crystal fluid that they eject 
