GALLS CAUSED BY MITES 
105 
make their blind leap. Perhaps the mite succeeds in 
‘ boarding ’ a passing insect which hovers near enough to 
fan it by the beating of its wings.”* 
Attacked buds may be at once recognized by their swollen 
and distorted appearance. The life-history of this mite has 
been fully investigated by Embleton, Collinge, Warburton, 
and other economic zoologists. A summary of their obser¬ 
vations, together with preventive and remedial measures, 
may be consulted in Leaflet No. 1, published by the Board 
of Agriculture and Fisheries. 
The Pear-leaf blister mite, Eriopliyes pyri Nalepa, is also 
on the increase in this country. It causes raised greenish or 
red patches or blisters on the leaves, and sometimes on the 
fruitlets. It is a very minute species, quite invisible to the 
unaided eye. It passes the winter under the outer scales of 
the buds on young shoots. “ It does not appear as an 
epidemic. Trees often remain unattacked in a garden, 
though in close proximity to badly infested trees.” For 
particulars concerning treatment of this pest, see Leaflet 
No. 239, Board of Agriculture. This mite attacks various 
other rosaceous plants, such as the Apple, Service tree, 
Mountain Ash, and the rare Cotoneaster vulgaris. 
On the Continent Eriophyes Kerneri Nalepa attacks various 
species of Gentiana; in all cases malformation and discolora¬ 
tion of the floral organs, often with “ doubling,” result, and 
the inflorescence of many Labiate plants is reduced and 
covered with a velvety pile under the influence of various 
mites, notably E. Thomasi , which infests many species. 
Theobald, in his first Report of economic zoology (1903), 
alludes to a phytoptid disease in violets, causing the leaves 
to curl tightly over at each side and become greatly 
deformed. The mites were green, and large enough to be 
seen easily with a hand-lens. Specimens were sent to 
Dr. Nalepa, who considered it to be a hitherto unrecognized 
species. He described it under the name of Eriophyes violae. 
* Alice L. Embleton, Knowledge, September, 1905, p. 234. 
