1897.] BLACK CURRANT GALL MITES 155 



new attack in the embryo buds. I wish I could tell you 

 more, but I do not see how to get at the point of locality, 

 excepting by watching shoots with a hand magnifier. I 

 really am quite at a loss as to what can be done. 



April 19, 1897. 



I wrote out to Vienna to Professor Dr. A. Nalepa, who is 

 the great authority on the Phytoptidce, and he is much 

 interested in hearing about this great spread of attack, but 

 is not able to give us better advice, as to practical remedies, 

 than what we are already trying. (See also p. 248.) 



He says very truly, that looking at the winter quarters of 

 the mite pests being most especially in the buds, such 

 measures as : 



(i) Breaking off and destroying the infested buds. J (2) 

 Cutting off the infested shoots just above the ground, and 

 so getting new shoots. (3) Only using uninfested pieces 

 for propagation could not, he thinks, fail to be of service, 

 if carried out carefully. I quite agree with Dr. Nalepa 

 so far as that, without these measures, infestation would be 

 worse than it is. In a small amount of growth (such as 

 bushes in a private garden), I can speak from my own per- 

 sonal experience of having sometimes satisfactorily checked 

 the spread of these or similar causes of injury by employing 

 dressings. But it is a very different matter where black- 

 currant bushes are grown by acres together ; and I greatly 

 doubt whether, even if consideration of cost were put aside, 

 it would be within possibility to get this wood (or grove) of 

 bushes, so examined and so expurgated of evil, as not to 

 leave centres for spread. 



It always strikes me as a very curious circumstance that 

 (so far as I am aware) the black currant is not affected by 

 this Phytoptus on the Continent, or at least in the large 

 part of it in which the attacks are noted by Kaltenbach 

 or Taschenberg. Do you think it can be that the black 

 currant is there of a somewhat different kind which repels 

 Phytoptus attack, just as some kinds of American vines are 

 not as subject as others to Ph\iloxera f It occurs to 

 me that it may be well worth while to import some hun- 

 dreds of plants and plant them, of course on what is 

 considered clean ground, and see what comes of it. I 

 should like your views after you have well thought the 

 matter over. I cannot expect the expense of an experiment 



1 This, or its equivalent, the immediate and diligent pinching of in- 

 fested buds with finger and thumb, has proved the most practical 

 remedy (Eo.). 



