71 



than that on which the insect reaches its maximum development. The 

 severe phase of attack by this bollworm begins in August, and in a 

 bad year almost all young green bolls and flowers, which are attacked 

 in preference to mature bolls, are found to be damaged. Experiments 

 therefore have been carried on to induce the ripening of a maximum 

 portion of the crop at the earliest possible time by progressively 

 withholding water from the plant to hasten maturity without sudden 

 change of conditions. At the same time attempts were made to render 

 the plant distasteful to the pest, which selects moist and shady positions 

 for o\T[position, by cutting away the upper shading leaves and branches 

 so as thoroughly to expose the heart of the plant to the sun's rays. 



The results of these experiments proved that the reduction of water 

 (\\'ithin the limits of experiment) does not result in a diminution of 

 ^aeld, does not damage the fibre, ripens the crop earlier, reduces the 

 boll-worm damage, ripens the crop more thoroughly, and thereby 

 lessens residues for boll picking. Further it was shown that topping 

 and stripping of leaves does not result in a diminution of yield, does 

 not damage the fibre and reduces the bollworm attack. 



The actual best conditions of watering must obviously depend on 

 climate and soil, but it may be generally stated that water should be 

 reduced after June to the minimum consistent with the health of the 

 plant, and withheld entirely after the first week in August. The 

 question of the best time for topping is also connected with climate, 

 time of sowing and nature of soil, and will require investigation for 

 each district. 



AsHBY (S. F.). Leaf-bitten Diseases of Coconuts. — Jl. Jamaica Agric. 

 Soc, Kingston, xxi. no. 7, July 1917. pp. 269-273. 



Leaf- bitten disease of coconuts is being followed in many places by 

 attacks of Mekimasius sericeus (striped weevil), which is attracted to 

 the rotting patches on the heart leaves. The life-cycle in Barbados 

 occupies 4 days for the egg, 7 weeks for the larva, 10 days for the pupa 

 and several weeks for the adult weevil, the larval being the injurious 

 stage. The adult, being an active flier, doubtless plays an important 

 part in spreading the disease by carrying the spores of the fungus on 

 its body. After treatment of the trees for the disease and as a 

 preventive to new infection that might attract the weevil, an ounce of 

 powdered arsenate of lead may be used to one gallon of Bordeaux 

 mixture, or the Bordeaux can be prepared with sea- water, using 

 20 per cent, more lime than with fresh water. 



DU BuYSSON (H.). Observations sur des Ny raphes de Coccinella septeni- 

 punctata, L. (Col.) parasit6es par le Phora fasciata, Fallen. (Dipt). 

 [Observations on the Nymphs of Coccinella sepfempunctata, L., 

 parasitised by Phora fasciata, Fallen.] — Bull. Soc. Entom. France, 

 Paris, no. 15, 10th October 1917, pp. 249-250. 



Observations on nymphs of Coccinella septempunctata taken on the 

 upper-surfaces of vine leaves showed them to be deformed owing to 

 parasitisation by a Dipteron, Phora fasciata. 



