THE LIFE-HISTORY OF THE BLACK-CURRANT GALL-MITE. Wh 
BIBLioGRAPHY. 
ERIOPHYES RIBIS, Westwood. 
Phytoptus ribis, Westwood, Gardeners’ Chronicle, 1869. 
Phytoptus ribis, Nalepa, Anz. Ak. Wien, xxx. p. 105 (1893). 
Eriophyes ribis, Nalepa, Das Tierreich, 1898. 
Though references to the black-currant gall-mite, and sugges- 
tions for its extermination, are frequent in the writings of 
economic entomologists, the serious contributions towards our 
knowledge of its life-history are few in number, and may here be 
conveniently summarized. 
1. Newsteap.—“ Recent Investigations on the Currant-bud 
Mite, Phytoptus ribis.” The British Naturalist, 1894. 
Eeg-laying commenced, Feb. 20. Thirty per cent. of the old 
infested buds dry by May 19. Mites found in the axils of the 
leaves on June 2. First found within the new buds on July 
27, with eges. Noobservations made during August. Migra- 
tion takes place during March. 
2. Warspurton.—“ The Black-currant Gall-mite, Phytoptus 
ribis, Westwood.” The Journal of the Royal Agricultural 
Society, 3rd ser. vol. vill. p. 754 (1897). 
Eggs found every month except December. Mites migrate 
during the spring, when slightly infested buds open and 
badly infested begin to dry up. No means of distribution 
except by crawling detected. Attempts to ascertain what 
became of the dislodged eggs unsuccessful. 
3. Witson.—“ Disease of the Black Currant caused by the 
Gall-mite (Phytoptus ribis).” Pamphlet issued by the 
County Council of Fife, Dec. 1898. * 
A few eggs found in December, numerous in February. 
Infested buds are dried up in July, before which time the mites 
wander. Distribution probably largely by wind, and perhaps 
by insects and birds, but no evidence offered in favour of this 
suggestion. 
EXPLANATION OF THE PLATES. 
Prats 33. 
Fig. 1. Twig of black currant showing diseased buds. From the apex to the 
point marked A is the current year’s growth ; between A and B is last 
year’s wood with the buds which shrivelled at the end of June 1901 ; 
below B is older wood with dry brown buds which dried in the 
summer 1900. 
