C 186 ] 
means gradually drawing the ruptured membrane, 
over the head and body, to the hind feet. During 
this operation, and for fome time after, by means 
of fomething glutinous, the fore part of the head 
adheres to the vent of the parent. Being thus fuf- 
pended in the air, it foon frees itfdf from the mem- 
brane in which it was confined’, and after its limbs 
are a little ftrengthened, is fet down on fome tender 
flioot, and then left to provide for itfelf. 
When the fpring proves mild, and confequently 
favourable to this kind of infedl, I have obferved 
not only the rofe trees, but various kinds of fruit- 
trees, to be greatly injured by them. Hence 1 was 
firfi; introduced to inveftigate the nature of thefe 
infers ; in order to find out fome expedient, where- 
by lo great an evil might be prevented. To avoid 
being tedious by defcending to particulars, I thall 
recommend the following general rule ; viz. to lop 
olf the infedled fiioots before thefe infedts are greatly 
multiplied j repeating the fame operation before the 
time their eggs are depofited. By the firfi; pruning, 
you will prevent a very numerous prefent increafe ; 
and by the fecond, may intirely cut olf the next 
year’s fiipply. 
SECTION II. 
In the fpring months, there appear on the rofe 
tree but two generations of Aphides, including 
ihofe which immediately proceed from the laft year’s 
eggs ; the warmth of the fummer adds fo much to 
their fertility, that no lefs than five generations fuc- 
ceed each other during that interval. One is pro- 
duced 
