NOTES ON RECENT RESEARCH. 



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attitude apparently so ill adapted to its structure. All the time its four 

 short legs would be waving wildly in the air. A number of mites standing 

 up in this way bore a remarkable resemblance to diminutive hydras with 

 greatly retracted tentacles. 



After indulging in this performance for a period varying from one to 

 five minutes, the mite would generally relax its rigid attitude, bring down 

 its feet to the surface again, and continue its progress by crawling, only 

 to resume its upright position and grotesque waving of legs a little 

 farther on. 



This behaviour was highly suggestive of a desire, on the part of the 

 mite, to attach itself to any passing object, and its readiness to do so was 

 easily proved in the most conclusive manner. If touched with a needle- 

 point, it immediately let go its hold on the bud and was carried off on 

 the needle. A camel's-hair brush or a feather applied to an infested bud 

 was found to be swarming with mites on subsequent examination. In 

 nature the most likely carriers of the mites would, of course, be insects or 

 arachnids. Accordingly spiders and insects of various kinds were either 

 induced to run over infested buds or examined after having been observed 

 to come into contact with them spontaneously, 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-spotted ladybird (Coccinella bipunctata), of the black ant 

 (Lasius nigcr), and of various 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 specially 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. 



With regard to the other sections of the summary similar information 

 has already been given in the Society's Journal,* which was apparently 

 overlooked by the authors, as no mention is made of the work in the 

 bibliography. 



The writers further state that if the results thus obtained are trust- 

 worthy certain inferences follow with regard to the treatment of the 

 disease. The most important are these : — 



"1. Any treatment of the ground under the infested bushes is 

 unnecessary, as the mites do not live in the soil." 



" 2. Spraying in the early spring is only calculated to destroy mites 

 which would perish in any case. 



" 3. The only time when spraying would be likely to prove beneficial 

 is at the end of May and the beginning of June, when it is undesirable on 

 account of the blossoms. 



" 4. The removal of all the new shoots from infested buds at the end 

 of June, if practicable, would apparently clear the plants of the disease. 

 * Newstead, Journal R.H.S., vol. xxv. Pt. III. 



