308 



14. Native varieties are uot a protection to domestic varieties. The fact that two 

 Yellow Mira Belle trees growing in the immediate vicinity of many natives had 65 

 per cent, of their plums destroyed by the curculio, while the natives had less than 

 10 per cent, of their fruit punctured, is sufficient proof of this. 



15. That succulent, quick-growing plums are not less attacked than slow-growing 

 varieties. 



16. The curculio develops readily in the Duchess apple. 



17. The curculio is not double brooded in Iowa, but the eggs deposited late in July 

 and August are from belated females. 



18. The two applications of London purple in water, although not made at the 

 time best suited to destroy the curculio, apparently gave a protection of 44 per cent, 

 against the ravages of this insect. 



19. London purple in water in proportion of 1 pound to 120 gallons is much too 

 strong a mixture for plum trees. One-half this strength is as strong a mixture as 

 should be used. 



Bulletin XXIII of the Cornell Station.*— Prof. J. H. Comstock and his 

 assistant, Mr. M. Y. Slingerland, publish this bulletin as joint authors 

 and devote it to the consideration of certain insects injuring the Pear, 

 Apple, Cherry, Current, Blackberry, and Raspberry. The insects 

 treated are the Pear- Leaf Blister Mite {Phytoptus pyri), the Stag Beetle 

 Borer on Pear {Dorcus parallelus), the Apple Bucculatrix, {Bucculatrix 

 pomifoliella), the Cherry-tree Tortrix {Cacceciacerasivorana), the Cherry- 

 tree Scallop Shell Moth {Hydria undulata), a Leaf-roller on Currant 

 {Cacoecia rosaceana), and SkBlsickherry Caue-hortr (Obereabimaculaf a). 



The bulletin is illustrated by sixteen figures, all but one of which 

 are new. The opening article is perhaps the most important contribu- 

 tion. The authors show that the mites live within the galls until the 

 drying of the leaves in the autumn, when they migrate to the leaf buds 

 at the ends of the twigs, where, after working their way beneath the 

 leaf scales, they remain through the winter. The remedy proposed is 

 to carefully prune and burn the young wood. This pruning should be 

 supplemented by carefully burning the fallen leaves and rubbish in the 

 orchard. The second article records the feeding of Dorcus parallelus 

 upon the tap root of a pear tree. The article upon the Apple Buccu- 

 latrix reprints the life-history traced by Mr. Brunn in 1881, and recom- 

 mends the spraying of kerosene upon the cocoons in winter and of Paris 

 green during June for the larvae. Under the head of the Blackberry 

 Cane-borer the fact is recorded that, after a careful pruning of infested 

 canes as soon as they had begun to droop, the insect was so completely 

 exterminated as to afford a perfect exemption for two years. 



* Cornell University, College of Agriculture. Bulletin of the Agricultural Experi- 

 ment Station. Entomological Division. XXIII. December, 1890. Insects injuri- 

 ous to fruits. 



