341 



shrewmice, hedgehogs, bats ; birds, including swallows and tomtits ; as 

 well as lizards, toads and various spiders. Among insects, Carabid 

 beetles are predaceous on the larvae of S. piileriana, cutworms and 

 Arctiids, and on Otiorrhynchus, which is also attacked by the larger 

 Staphylinids. The larvae of Malachiid and Clerid beetles prey upon 

 the larvae and pupae of vine-moths hibernating under the bark. 

 Coccinellids destroy the Coccids and the young vine-moth larvae. 



Among predaceous Hymenoptera, Eunienes and Odynerus provision 

 their nests with young larvae of Haltica ampelophaga, Ammophila spp. 

 attacking the caterpillars of Noctuids, and Cerceris spp. preying on 

 Otiorrhynchus. Parasitic Hymenoptera include the Ichneumonids, 

 Ichneumon melanogonus, parasitic on S. piileriana, and Pimpla alter- 

 nans and Agrypon flaveolatmn, parasitic on all three vine-moths ; the 

 Braconids, Microgaster (Apanteles) cajae attacking Arctia caja, Meteorus 

 pallidus infesting cutworms, and Perilitus brevicollis, an enemy of 

 Hallica ampelojyJiaga ; the Chalcidids, Pteromahis spp. attacking the 

 larvae of S. piileriana, 31o7iodontamerus aereus those of C. ambiguella 

 and P. botrana, and Oophthora semblidis parasitising the eggs of all 

 three species. 



Dipterous parasites include the Tachinids, Degeeria funebris, para- 

 sitic on H. ampelophaga, Parerynnia vibrissafa on S. piileriana, and 

 Echinomyia prompta on the caterpillars of Noctuids. BacilU and fungi 

 also play a part in the control of vine insects, Arctiid larvae being 

 attacked by Bacillus cajae and Empusa aidicae. Adults of Haltica are 

 attacked in winter by Sporotrickum globuliferum, and the chrysalis of 

 C ambiguella by Isariafarinosa. 



The technique of the various treatments is described. Winter 

 decortication has for its object the removal and destruction of the 

 old bark in order to destroy the insects which it shelters. To be 

 successful, a sheet should be spread on the ground with a hole cut in it 

 for the stock. Hot-water treatment is applied in winter by means of 

 a boiler mounted on a cart which contains boiling water ; this is 

 sprayed over the branches, either by means of rubber tubes connected 

 with the boiler and supplied with jets, or by cafetieres with double 

 walls. The liquid repellents or insecticide sprays recommended have 

 already been described [see this Review, Ser. A, iv, p. 299]. In prepar- 

 ing arsenical sprays, it is now necessary to buy arsenate of lead in the 

 form of a prepared powder or paste which is simply diluted in water. 

 The proportion of arsenate of lead contained in these commercial 

 products varies according to the brand, and this should be ascertained 

 before preparing the mixture. For example, the quantity of neutral 

 arsenate of lead required to be used compared with that of disodic 

 orthoarsenate is about 2*4 times as much, i.e., one oz. of disodic ortho- 

 arsenate of lead when completely transformed into neutral arsenate 

 of lead gives 2'4 ozs. of this salt. Therefore the old formula, anhydrous 

 sodium arsenate 2 lb., neutral lead acetate 6 lb., water 100 gals., would 

 correspond to 2 x2-4 = 4-8 lb. per 100 gals., or with the formula con- 

 taining 3 lb. anhydrous sodium arsenate, 7-2 lb. per 100 gals. In 

 round figures, an arsenical mixture based on lead arsenate should 

 contain 5 to 7 lb. of this salt per 100 gals., the greater strength being 

 the more usual. Many of the commercial preparations sold for the 

 purpose of making arsenate of lead sprays may be recommended, but 

 in order to obtain the necessary 5-7 lb. of lead arsenate per 100 gals.. 



