288 JOUENAL OF THE ROYAL HORTICULTUKAL SOCIETY. 
and are still being carried on ; but the result up to 1900 has been published 
in the "Second Report of the Woburn Experimental Fruit Farm"* 
(pp. 7-34), which should be in the hands of all who are interested in this 
matter. 
In the Journal of the South- Eastern Agricultural College, Wye, 
Kent, is a preliminary report by Mr. H. H. Cousins on some experiments 
on the fumigation of infested Currants with hydrocyanic acid, a treatment 
which has of recent years found much favour as an insect destroyer.t 
In treating of the efficiency of various suggested remedies, I shall have 
occasion to refer to the works mentioned above, with due acknowledgment 
to their authors ; but in other respects I shall confine my remarks to my 
own observations. 
Appearance of the Diseased Buds. — The difference between a healthy 
branch of Black Currant and one which is diseased is clearly shown in 
the accompanying photograph (fig. 157 a, b). At " a " is a typical healthy 
branch, and at " b " one which is badly infested with mites. In the former 
the buds are comparatively small and pointed ; while the buds of the latter 
are much swollen and rounded, and usually from two to four times larger 
than those which are free from mites. If a longitudinal section of the 
buds be made, it will be seen that in the healthy ones (fig. 158) the embryo 
leaves, forming the outer layer, are regularly placed, and hermetically 
close the apex ; while the corresponding leaves in the diseased bud (fig. 159) 
* Second Report of the Wohurn Experimental Fruit Farm, 1900. His Grace the 
Duke of Bedford and Hpencer U. Pickering, F.R.S. London : Eyre & Spottiswoode. 
f This report will be found on page 303 following. See also B.H.S. Journal, 
vol. xxiii. p. 346. 
S 
Fig. 158 Section through a 
Healthy Bud x 6. 
From a photograph. 
Fig. 159. — Section through an 
Infested Bud x 6. 
From a photograph. 
