854 
Cultivation and Management of Hops. 
of lice swarming on the under surfaces of the leaves.* The pores 
of the leaves are soon choked up, the exuviae of deceased genera- 
tions adhere to the sticky fluid ; and the oxygen of the air, acting 
upon the whole, soon turns a green flourishing hop-ground into 
a black mass of desolation. Until the last few years, no remedy 
had been discovered at all successful or satisfactory. Some burned 
green faggots, or heaps of green rubbish, weeds, bushes, or turf, 
to windward of their plantations, that the smoke might stifle the 
invaders ; some threw lime, rape-dust, or powdered tobacco over 
the plant ; some, as has been noticed before, tried to starve out 
the intruders through the diminution of the sap of the plant by 
excessive cultivation. By ' Kirby and Spence ' the hop-growers are 
censured for their ignorance of entomology and their supineness, 
because they did not set persons with ladders to catch, and. 
crush " between the thumb and finger,"f the aphides (fly) which 
first make their appearance. This astonishing advice is gravely 
repeated by Mr. Wood in his work called ' Our Garden Friends 
and Foes.' Hop-growers have tried a good many absurd experi- 
ments to stop a blight, but, to their credit, it must be said that they 
never attempted such a wild-goose crusade. Washing or squirting 
the bine all over with water, soft soap, and sometimes tobacco- 
juice, is the best means of prevention, and is tolerably efficacious 
if the operation is carefully performed by the workmen and judi- 
ciously timed by the grower. It is a mistake to begin washing 
upon the first appearance of fly, as, if they are washed off to 
the ground, they may recover and fly up again, or others later 
hatched may take their places. When the great green lice are 
reproducing their kind by the process of " gemmation " — 
believed to be an unique instance as regards insects % — one 
washing, if thoroughly done, causes great slaughter and may 
clear the plant thoroughly. The washing may be repeated at 
intervals of ten days, once or twice if necessary ; but it must not 
be done while the plant is in " burr," or bud, nor when the flower 
is beginning to ripen, lest the " condition " or farina be injured. 
The process of washing is carried out by means of a common 
large garden engine, with a pump and a long gutta-percha 
hose on each side, fitted with a simple jet and rose, or "spray " 
* " By means of a lens we have actually seen the aphides ejecting the honey- 
dew." — (Knight's ' Library of Knowledge — Insect Transformation,' p. 19.) 
t Kirby and Spence's ' Entomology,' p. 101, seventh edition. 
X " The apbis is capable of propagation by a process that appears to be analogous 
to the gemmation of the salpoe : the new individuals being budded olF, so to speak, 
from internal stolons, instead of being developed from ova provided by the female, 
and fertilised by the male. This method of propagation may be several times 
repeated ; the individuals thus generated being all apparently of the female sex 
and generating others like themselves." — (Dr. Carpenter's ' Principles of Physio- 
logy,' p. 38.5.J 
