844 
ANNUAL REPORT OF NEW YORK 
Arms. COOCINELLA LARVA! STARVING EAT THEIR OWN SPECIES. 
those of the parent insect and with those of the species of this 
famity generally. Many persons I doubt not have noticed the 
peculiar manner in which these lady bugs travel about upon 
plants, without being at all aware of the object of their jour- 
neyings. They move with more or less agility as they are more 
or less pressed with hunger, some species being always more 
active and sprightly in their motions than others. 
Searching for plant lice, one of these insects will be seen to 
walk briskly up a plant to its very summit. You expect it will 
now take wing or will pause a moment to consider what to do 
next. But no; finding nothing, it abruptly turns about and 
walks back with the same pace that it ascended, till coming to a 
branch or a leaf it goes out upon this, travelling along its under 
side to its end and then immediately turning back without any 
pause and out upon another. Thus it industriously walks over 
the whole plant, scarcely an}^ part of a leaf or a stem where plant 
lice will be liable to occur escaping its examination. Its forag- . 
ing being unsuccessful here, it descends to the ground and coming 
to another plant mounts and examines it in the same manner. 
These larvae of all sizes were quite numerous in the stubble of 
the grain fields after harvest. They speedily consumed the few 
grain lice which had been scattered off upon the straws and weeds 
remaining in the fields, and then becoming pressed with hunger 
they were seen running wildly about, everywhere, in search of food. 
When reduced to such straits they became cannibals, devouring 
the helpless of their own species. If one of them chances to meet 
another which has suspended itself preparatory to changing to a 
pupa and is thus become incapable of resistance, it does not hesi¬ 
tate to devour its defenceless fellow. The suspended larva when 
thus attacked passively submits to its doom, without any strug¬ 
gling or writhing, to impede its murderer in his work, as if con¬ 
scious it was wholly unable to avert its fate. Its assailant eats 
a hole in one side and then consumes all the soft inward parts, 
leaving nothing but the skin of the two ends slightly connected 
by what remains of the middle. But the fully formed puprn are 
never attacked, their substance being so changed, no doubt, that 
it has ceased to be nourishing food for the larva. 
But though these larvae thus eat one another they will not eat 
the larvae of other insects, nor any plant lice except those of par¬ 
ticular plants. I introduced the larva of a wheat midge to a 
