180 Annual Report for 1905 of the Zoologist. 
The new buds are now ready, and the few mites which are 
fortunate enough to reach them set up the new attack. They 
travel partly by crawling, partly by leaping, and largely by 
adhering to passing insects. Probably the currant aphis does 
more than any other insect to spread the disease, as the winged 
individuals will fly directly to another currant bush, whereas 
a casual insect visitor might carry the mites far from their 
natural food. 
The mites which do not reach the new buds either perish or 
have some way of sheltering in the ground or low down on the 
plant. Reasons have been given above for believing that some 
at least do occasionally find a hiding place in the lower part of 
the stem, and that the rest all die. 
The conclusions are clear, if not comforting. There is no 
likelihood of exterminating the pest except by exterminating 
the diseased bushes. A creature so minute and so well hidden 
is bound to survive the most drastic treatment in sufficient 
numbers to set up a new attack, for a single living mite in a 
young bud may start the disease afresh. 
The disease may certainly be mitigated — if this result is 
worth aiming at — though the life-history given above indicates 
that many of the measures ordinarily adopted are so much 
waste of money, as they are calculated to kill the mites which 
would in any case die. There is no doubt that by uprooting 
and burning badly infested bushes, removing “ big buds ” from 
those slightly attacked, and washing during the migrating 
period, a tolerable crop may be obtained from diseased plants 
for several years ; but it must once more be pointed out that if 
growers are contented with this result there will, before long, 
be no mite-free plants to be obtained. As things are at present, 
nurserymen will not guarantee plants to be free from mite, but 
introduce at intervals so-called disease-resisting varieties, which 
always succumb sooner or later. 
Growers content themselves with getting what fruit they can 
from a diseased plantation, grubbing up the plants when they 
cease to yield a paying crop, and replacing them with young 
plants from the nurseries, free from any obvious “ big buds,” 
but often quite sufficiently diseased to develop very clear 
symptoms a year or two later. The only people who can do 
anything to alter this state of things are the fruit growers, and 
the first step must be to insist on getting cuttings taken only 
from entirely mite-free plants. The universal habit of pro- 
pagating from plants which are diseased — though perhaps very 
slightly — is rapidly spreading the mite everywhere. As has 
been stated before in these Reports, a few years ago there was 
no big bud disease in Co. Armagh, but when an increased 
demand for fruit caused many growers to purchase new plants 
