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CURRANT. 
Black Currant Gall-mite. Phytoptus ribis , Westwood. 
Phytoptus (? sp.). 
Gall-mite and egg, enormously magnified. [Infested Birch buds.*] 
The PhytojJti, or Grail-mites, are excessively small creatures of the 
shape figured, which live together in large numbers, and give rise to 
diseased plant-growth, often in the shape of galls on the leaves, some¬ 
times, as in the case of the Black Currant, Nut, and Birch, by causing 
an abortive growth of the leaf-buds. 
They are not true insects, but, like the “ Spinning-mites ” (the so- 
called “Red Spiders” so injurious to the Hop leafage), belong to the 
order of Acarina, or Mites. The subfamily of the Phytoptidce are dis¬ 
tinguishable by their peculiar long, somewhat cylindrical, shape, and 
by having only two pairs of legs placed close together beneath the fore 
part of the body, which ends in a kind of conical projection containing 
the mouth-parts. The details of those of the Black Currant Gall- 
mite have not been described (so far as I am aware), but those of the 
Pear-leaf Gall-mite consist of excessively fine sword-shaped jaws fitting 
on each like scissor-blades,f these being contained, with other minute 
apparatus, in the somewhat conical proboscis. 
The skin is much wrinkled across, and the mite, besides its two 
pairs of legs, is furnished with various large bristles, regarding the 
nature of which there has been much discussion. The creature, 
being excessively minute (so that the smallest dot visible to the naked 
* The buds on the Birch shoot show the form, though not the arrangement, of 
those on the Black Currant shoots. Not having command of a figure of Black 
Currant attack the above is given, with further explanation in the following paper, 
as being clearer than mere description. For figures of seven kinds of Phytoptus 
attack, by Editor, including that on Black Currant, see ‘ Economic Entomology : 
Aptera,’ by A. Murray, article “ Gall Mites,” pp. 355—361. 
t For further details of the Pear Gall Mite, see * Der Milbensucht der Birnbaume,’ 
von Paul Sorauer. 
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