344 



stems of Jasminum and young lime trees ; Aspidiotus palmae, Ckll., 

 recorded for the first time from the British Isles, occurring freely on 

 the Bromehad Keratas ; and Orfheziola vejdovskyi, Seele, found in moss. 



Rice (W. H,). Red Mite and Woolly Aphis on Nursery Fruit-Trees. — 



New Zealand Jl. Agric, Wellington, xx, no. 4, 20th April, 1920, 

 pp. 250-251. 



Control tests against Tetrangchus and Eriosoma lanigermn on orchard 

 nursery stock confirmed the results of those already noticed \R.A.E., 

 A, vii, 357] ; but red mite control cannot be assured with red oil weaker 

 than 1 : 6. Root immersion in oil of apples and pears is not injurious, 

 but in the case of plums it retards bud-movement fully a week, though 

 there is no other damage. 



€aesar (L.) & Gaelick (G.). The Imported Currant Worm, Pteroniis 

 ribesii, Scop. — Canad. Entom., London, Ont., hi, no. 5, pp. 106-108. 



Attention is drawn to some points of interest observed during a 

 study of the imported currant sawfly, Pleronus ribesii, Scop. The 

 food-plants of this insect are generally referred to as " currants and 

 gooseberries," but as a matter of fact, red and white currant foliage 

 is attacked but never that of black currant. Oviposition was observed 

 when the leaves were very young, in fact when the majority of the 

 buds had just burst. Parthenogenesis is common in this species, the 

 adults derived from unfertihsed eggs being invariably males. The 

 eggs are laid in a chain-hke arrangement along the main ribs or veins 

 on the under-surface of the leaves in the central and lower pa^'t of the 

 bush, and the younger larvae frequently strip that portion of leaves 

 before their presence is detected. The later generations o\dposit 

 inther indiscriminately over the leaves. The second generation larvae 

 begin to hatch about a weeV: before red currants are ripe and hatching 

 continues for about a month. The third generation begins to hatch 

 about two weeks after- the fruit has ripened. The adults producing 

 this generation emerged in cages up to September. FuUy half the 

 larvae of the two earlier generations remained in cocoons throughout 

 the year without pupating. Many larvae of the second and thii'd 

 generations die soon after hatching and do httle damage, so that if 

 the first generation can be destroyed little harm will result. 



Natm-al factors in control include two parasites, one a Braconid and 

 the other a Cynipid ; many eggs are destroyed by Chrysopids and 

 Coccinelhd larvae. Another cause of mortality is the heat of the 

 soil, which kills many larvae that fall upon it accidentally or when 

 seeking pupation quarters. Artificial control is easy. Against the 

 young larvae, |lb. lead arsenate paste in 40 gals, water is efiicacious. 

 If the bushes are thoroughly sprayed as soon as the leaves are well- 

 developed, especially in the central and lower part of the bush, with 

 1-2 lb. lead arsenate paste or | to 1 lb. powder in 40 gals, water, no 

 damage should result. If Bordeaux mixture is used, calcium arsenate, 

 a httle weaker than the lead arsenate, may be used, or not more than 

 ^ oz. of Paris green may be substituted, in 40 gals. Bordeaux. If 

 a second spraying is necessary it should be given eight or ten days 

 after the first, or soon after red currants are well set. 



