651 



to the Chalcid. In dry districts the fungi are active only in the wet 

 seasons ; in these districts trees should be sprayed at least twice 

 between spring and summer rains, and an attempt should be made a 

 few weeks later to reintroduce the Chalcid and mite from unsprayed 

 trees. Twigs bearing the fungi should be introduced at the beginning 

 of the rains. 



Aleurocanthus woglumi, Quaint., has become abundant on the leaves 

 of all species of citrus. The eggs are laid on the under surface of the 

 leaves. The larva hatches in about 14 days and reaches maturity 

 about 29 days later ; the pupal stages lasts at least 3 weeks. 

 During January to March 1913, the complete life-cycle from egg to 

 egg occupied at least 9 weeks. In warmer months development is 

 more rapid ; at least 5 broods are produced annually and there is no 

 pariod of hibernation. Severe infestation checks growth and has a 

 marked effect on the setting and size of the fruit. In 1914 fungus 

 parasites were found in the larvae ; the most effective kinds were 

 a red non-spore-bearing species (brown fungus of Florida) and a 

 species apparently identical with Aschersonia aleurodis. The larval 

 stages are probably most susceptible to an oil emulsion spray when 

 moulting. Since mango is also infested by this insect, it must be 

 sprayed if grown near citrus trees. A list of fungicides and insecticides 

 is appended. The following formulae are recommended : — (1) kerosene 

 emulsion : ^ lb. soap, 1 gal water, 2 gals, kerosene, 1 gal. stock solution 

 to be diluted with 10 or 15 gals, water ; (2) lime-sulphur wash : 15 to 

 20 lb. stone lime, 15 lb. flowers of sulphur, 50 gals, water. A mixture 

 of 3 parts flowers of sulphur and 1 part air-slaked lime is useful against 

 red spider on citrus, vine and sweet potato. 



Ritchie (A. H.). Economic Entomology in Jamaica. — Bull. Dept. 

 Agric, Jamaica, Kingston, ii, no. 8, 1915, pp. 335-338. 



The necessity for co-operation between official and planter in order 

 to further the interests of agriculture in Jamaica is urged. Economically 

 sound and practical measures, recommended after thorough con- 

 sideration, should, if necessary, be backed by legislation. In 

 entomological work in the Colonies the question of freight on insecticides 

 may be an important item in considering the value of certain measures 

 of control. Concentrated lime-sulphur solution is a valuable contact 

 spray material against rust mite, red spider, etc., which falls under 

 this category. So far, attempts to produce this in an effective solid 

 form have failed. Experiments with barium as a base have shown 

 that one at least of the polysulphides of barium, viz. barium tetra- 

 sulphide, can be producecl in a soluble crystalline form. Opportunity 

 will be taken to test the Bordeaux-nicotine sulphate spray against 

 thrips and pod-rot of cacao. The use of quassia decoction as a contact 

 spray has long been known. As Picroena excelsa, Swz. (bitter wood) 

 grows in abundance in Jamaica, the effectiveness of a decoction of it will 

 be investigated. In California good results have been obtained against 

 certain Aphids with a mixture consisting of 3 lb. quassia, 3 lb. whale 

 oil soap, and 100 gals, water. 



