457 



Direct remedial measures did not appear feasible, but in time the 

 infestation proved to be less serious than at first thought, only the 

 weakest and backward plants dying. The healthy plants recovered, 

 and the openings of the mines closed up. In sections of such stems the 

 discoloured mines were visible and here and there the dead insects were 

 enclosed. Preventive measures are advocated, the immediate 

 destruction of prunings by burning being one of these. When pruning, 

 some of the twigs should be spared so as to regulate the sap-flow and 

 promote the speedy growth of the tissues, in order that the mines may 

 become closed. 



Bernard (C). Verslag van het Proefstation voor Thee over het 

 Jaar 1919. [Report of the (Buitenzorg) Tea Experiment Station 

 for 1919.] — Meded. Proefstation voor Thee, Buitenzorg, no. 69, 

 1919, 23 pp. [Received 24th August 1920.] 



The section on diseases and insect pests in this report is embodied 

 in one already noticed [R.A.E., A, viii, 329]. Among the papers 

 issued were some on Helopeltis [R.A.E., A, vii, 499, 500]. Work is 

 now in progress on the tea leaf -rollers, Gracilaria theivora, Wals.,. 

 Cydia (Laspeyresia) leucostoma, Meyr., and Homona coffearia, Nietn. 

 Experiments in the control of Helopeltis are being conducted. 



Senior-White (R.). A Note on Suana concolor, Walker. — Spolia 

 Zeylanica, Colombo, xi, no. 42, 22nd July 1920, pp. 299-302, 1 

 plate. 



The Lasiocampid, Suana concolor, WUv., occurs in India, Ceylon, 

 Java and the PhiHppines. Its food-plants include Psidium guayava, 

 Cajanus indicus. Hibiscus rosa- sinensis, Greivia tiliaefolia and Shorea 

 robusta. It is said occasionally to attack tea in Ceylon. 



In the [Matale] district the author has observed two broods a year, 

 maturing in February-March and September, respectively. The egg, 

 larva, pupa and adult are described. 



All stages of the larva are attacked by a fungus, Verticillium sp. ; a 

 species of Penicillium found on dead larvae is believed to be a secondary 

 parasite. A Phorid fly has been seen to emerge from dead larvae, in 

 which it appears to oviposit before they die from some other- cause. 



CoAD (B. R.) & Cassidy (T. P.). Cotton Boll Weevil Control by the 



Use of Poison. — U.S. Dept. Aqric, Washington, B.C., Bull. 875, 

 July 1920, 31 pp. 



The system of poisoning described in this bulletin does not aim at the 

 extermination of the boll-weevil [Anthonomus grandis], but only at a 

 sufficient reduction of infestation to permit the maturing of a full crop 

 of cotton. This depends on the habit of the cotton plant of producing 

 much more fruit than it is able to mature. About 60 per cent, of 

 the squares fail to reach maturity as bolls, and are shed at some time 

 during their development. This shedding is comparatively slight 

 early in the season, and increases rapidly as the plants develop, until 

 it reaches the point when all the new fruit that appears is shed. Up 

 to a certain point the fruit shedding due to boll-weevil attack merely 

 takes the place of the normal shedding which would occur even if the 

 weevils were absent. 



