835 
No. 145.] 
it, and returns to guarding his flock of aphides, till another of 
the small ants approaches, which is similarly seized, but with the 
same result as before. After two or three such encounters he 
seems to suspect that some mischance has thrdwn him out of his 
proper latitude, and he walks around to take a survey of the 
parts adjacent. He no sooner leaves the flock of lice than one of 
the small ants hastens to them and rapidly passes its sting around 
among them, hereby marking them as its own property. From 
that moment the large ant ceases to notice them, and the small 
ones gather around and commence rubbing and nursing them as 
attentively as though they were old acquaintances. It is evidently 
the pungent fluid of their stings which they throw around among 
the aphides which render them repulsive to the large ant; and 
when he first seized one of these small ants it was the suffocating 
fumes of this fluid which induced him to drop his victim so 
hastily, for their sting is not powerful enough to penetrate the 
hard horny outer surface of his body. 
It is somewhat remarkable that, so closely related to each other 
as the different kinds of cherry trees are, the aphides which in¬ 
fest one of these kinds of trees do not establish themselves upon 
the others also. Yet we never see the black aphis of the garden 
cherry invading any of our native or wild cherry trees, and the se 
appear each to have a species of plant-lice peculiar to them which 
seldom if ever fix themselves upon the foliage of the other kinds? 
Thus a species which I described in the Fourth Report of the 
State Cabinet, page 65, under the name of the cherry-inhabiting 
aphis [A. Cerasicolens), pertains to our common black cherry. 
Another species may here be noticed which infests the under sides 
of the tender apical leaves of the choke cherry, curling their 
margins downwards and inwards, and changing them to a paler 
yellowish green color. It may Ije named and characterised as 
follows: 
The Cherry Leaf Plant-iouse (Jphis Cerasifolia ), measures 0.08 to the tip of 
its abdomen, and 0.15 to the end of its wings, which expand 0 26. It is black with a 
pale green abdomen, which has three dark green dots on each side forward of the necta. 
nes, and above these a row of impressed deep green dots extending backwards past 
16 " Bc,ane » with a deep green stripe upon the middle of the back which does not 
reach to the tip; the sutures are also of a deeper green color; the nectaries reach 
