370 MR. GC. WARBURTON AND MISS A. L. EMBLETON ON 
taneously, and in almost every instance mites were found attached 
to their bodies or appendages. The fact was recorded of four 
different species of spider, of the larva of the currant-moth 
(Abraxas grossulariata), of the currant Aphis, of the larva of the 
two-spot ladybird (Coccinella bipunctata), of the black ant 
(Lasius niger), and of various other insects. So uniform was 
the result, that the investigation into the various creatures 
capable of distributing the mite was presently discontinued, as 
it was clear that almost any insect might perform that function, 
though those which wander widely and especially affect currant- 
bushes would necessarily be most efficient. It is probable that 
the currant Aphis is especially instrumental in spreading the 
disease. It crawls slowly along, feeling its way with its antennae, 
to which the mites readily attach themselves, and the winged 
individuals would be extremely likely to convey the pest direct 
to another currant-bush. 
Method of Attachment. 
The mites do not seem in any true sense to grasp the objects 
presented to them, nor, indeed, do they possess any prehensile 
organ, unless the tail-dise may be placed in that category. 
Moreover, ordinary hairs and bristles are much too thick, rela- 
tively to the mites, for seizure by means of the jaws or legs. 
Attachment always seems to take place, in the first instance, 
simply on account of some adhesive substance with which the 
bodies of the animals are coated. 
A mite may be removed by any portion of its body being 
touched by the antenna of an aphis, but it quickly coils itself 
round the appendage in a worm-like fashion and brings its tail- 
dise into play. 
Possibly the bristles and ‘‘ feather-hairs”’ (Pl. 33. fig. 8) on 
the legs of the mite may to some degree entangle themselves 
among the fine hairs on the bodies and legs of insects. When 
removed on acamel’s-hair brush the mites wriggle in and out 
among the hairs and soon secure a tolerably firm hold. 
Leaping. 
While the behaviour of the upright mites was under observa- 
tion under the microscope, it was noticed that individuals some- 
times disappeared from the field of view with a suddenness that 
made it impossible to see what precisely had happened. This 
