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Slugs and Snails and,.moreover, is beneficial to the plants. 
Natural enemies are {lso an important factor: thrushes, 
blackbirds, starlings, and also ducks and fowl render help 
in keeping down an excess of Slugs and Snails. 
Among other injurious animals WOODLICE (8) and 
MILLIPEDES (7) were also referred te but, owing to the 
limited space at my disposal, I must pass over these and 
deal with the Acari or MITES. They are classified as a 
group of the Arachnida, which also includes Spiders, 
Harvestmen, and Scorpions. All can be recognised by 
the presence of eight pairs of legs, the absence of feelers 
or antennae, and the fusion of the head and thorax into 
one compact region or cephalothorax. Acari are further 
distinguished by the abdomen not being definitely marked 
off from the rest of the body. The Red Spiders or Trom- 
bididae belong to this group, but the most important for 
our purpose are the Eriophyidae or Gall Mites. £7zo- 
phyes ribis (4) or the BLACK CURRANT GALL MITE is 
responsible for the “ Big-Bud” disease which has spread 
throughout the country. Its presence can be readily 
detected by the swollen and distorted appearance of the 
buds which harbour the Mite. Badly infested buds sel- 
dom develop into shoots, they remain unopened and, after 
retaining their green colour for a time, become brown and 
die off. The damage is caused by the jaws of the Mite 
cutting through the epidermis of the delicate young leaves, 
followed by the inserting of the sucking tube which 
extracts the sap. Throughout the winter the Mites feed 
and shelter in the galled buds. Migration takes place from 
the infected buds, which open from about the middle of 
April until well on in June. The Mites then crawl out 
in great numbers in order to find new and succulent buds 
to serve for their future sustenance. This migration 1s 
aided by the habit the Mites possess of often attaching 
themselves to passing insects wandering over the twigs. 
By this means they become distributed to other branches 
and to fresh bushes. Strong winds are also a factor aid- 
ing their dispersal. Having entered new buds the Mites 
commence laying their eggs and thereby multiply rapidly 
until the end of the summer. Shoots examined during the 
end of August and in September, exhibit the “ Big-Bud ” 
appearance, and are filled with the new generation of the 
Mite, which will carry on infection for the next season. A 
certain number of eggs are to be found all the year round 
