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lumps and is probably rendered unfit for fertilisation of the female 

 flowers. Very scanty crops of nuts are obtained from palms infested 

 with this mite, which is frequently found associated with the coconut 

 spike caterpillar. Where treatment is necessary, dusting each spike 

 as it opens with flowers of sulphur, or spraying with lime-sulphur, 

 would probably prove satisfactory. Brachartona catoxantha is a 

 recurrent pest, the larvae causing serious damage at intervals of from 

 two to six years. In the interim they are kept in check by parasites, 

 of which a Tachinid fly appears to be the most important, while a 

 fungus, Botrytis sp., probably acts as a further check. The caterpillars 

 of B. catoxantha eat away narrow strips of tissue on the under-sides of 

 the leaves, all except the youngest leaves of the crown being entirely 

 destroyed in bad infestations. Moreover the wounds in the leaves 

 made by the insect encourage the attacks of leaf fungi, such as 

 Pestalozzia. Spraying with a combined insecticide and fungicide 

 might be a successful control measure, but since palms are not 

 apparently killed outright by B. catoxantha, it is not known whether the 

 value of the crop saved would compensate for the labour and expense 

 involved in this method. The fact that leaf fungi thrive in wet weather 

 and are not likely to cause much damage during a drought must be 

 considered in deciding whether or not to use a fungicide, while spraying 

 should be regulated by the numbers of parasites present, which differs 

 in different outbreaks. It is therefore impossible to lay down any 

 hard and fast rule for treatment. The larvae of various species of 

 Psychid moths (bag-worms) have occurred as local pests on coconuts 

 and have done much damage in small areas. Treatment consists 

 of hand-picking the cases or poisoning the young caterpillars with a 

 poison spray. 



Coffee growers should keep a watch for Cephonodes hylas (coffee 

 clearwing moth), the caterpillars of which have been taken frequently 

 on coffee and Gardenia. 



Ross (W. A.). The Pear Psylla. — Agric. Gaz. Canada^ Ottawa, v, no. 

 12, December 1918, pp. 1134-1136, 10 figs. 



A popular account is given of Psylla pyricola (pear psylla), which 

 is frequently very destructive to pear orchards in Ontario. The 

 life-history and nature of the injury are described. The increase of 

 the pest is checked to some extent by several insect enemies, notably 

 Coccinellids, but the most important factor is undoubtedly the weather. 

 Protracted periods of cold, wet weather in spring may be disastrous 

 to the eggs and newly hatched young, while long periods of hot dry 

 weather are fatal to many nymphs. In Ontario it has been found 

 most satisfactory to postpone the so-called dormant application of 

 lime-sulphur (winter strength) until shortly before the trees bloom 

 and then thoroughly drench all parts of the trees including the under- 

 side of the twigs and branches. This destroys the newly hatched 

 nymphs and the eggs about to hatch. Nicotine sulphate, 40 per 

 cent., is added at the rate of f pint to 80 gals, spray mixture applied 

 just after the blossoms fall. This kills the nymphs which are then 

 chiefly in the axils of the leaf -petioles and blossom- stems. 



