569 



Headlee (T. J.). Dusting v. Spraying for Insect Control.— Trans. 



Peninsula Hortic. Soc. [Delaware], xxxiv, 1921, pp. 51-60, 1 fig. 

 (Abstract in ExpL Sta. Record, Washington, D.C., xlv, no. 2, 

 August 1921, p. 137.) 



This paper records experiences of dusting and spraying for the 

 control of insect pests in New Jersey during 1919 and 1920. \ chart 

 illustrates the relation of rainfall in these years to the time of application 

 of dusts and the periods during which such applications must remain 

 on the tree to be effective. Heavy rains were found to wash off the 

 dust promptly and light rains to be harmful when extending over a 

 long period. A marked correlation existed between the presence or 

 absence of- heavy rains and the number of larvae of the codling moth 

 [Cydia pomonella]. 



The author concludes in part that the best that can be claimed for 

 the dust under most favourable average conditions is that it is about 

 as good as the spray. In New Jersey the evidence in favour of greater 

 efficiency on the part of the liquid materials is clear and definite for 

 control of curculio [Conotracheltis nenuphar] and codling moth. 



RoHWER (S. A.). Notes on Sawflies, with Descriptions of new Genera 

 and Species. — Proc. U.S. A^at. Mus., Washington, D.C., lix, 

 no. 2361, 1921, pp. 83-109. 



The new species of sav^rflies described include Xiphydria chanvplaini 

 reared from wood of Carpimis caroliniana from Pennsylvania, X. 

 heritierae reared from sundri {Heritierafomes) from Bengal, Neodiprion 

 eximina reared from larvae collected on Pinns resinosa in Wisconsin, 

 and Senoclia dioscoreae on Dioscorea from India. 



ViERECK (H. L.). First Supplement to " Type Species of the Genera 

 of Ichneumon-flies." — Proc. U.S. Nat. Mus., Washington, D.C., 

 hx, no. 2364, 1921, pp. 129-150. 



This supplement completes the author's review of the literature 

 on the Ichneumonoidea [R. A.E., A, ii, 182] up to the end of 1919. 



Weld (L. H.). American Gallflies of the Family Cynipidae producing 

 Subterranean Galls on Oak. — Proc. U.S. Nat. Mus., Washington, 

 D.C., hx, no. 2368, 1921, pp. 187-246, 10 plates. 



The object of this paper is to bring together the scattered existing 

 information with regard to the American C\mipids forming root-galls 

 on oaks. Twenty-three new species are added to the seven previously 

 described, and several changes are made in the synon\any. 



It is thought that further study of the relationships of the gall-making 

 Cvnipids to their foodplants will throw light on the affinities of the 

 species of oak. Whereas some Cynipids attack many oaks, others con- 

 fine themselves to a single species ; thus one species dealt with attacks 

 at least ten species of the red oak group and probably more, whilst 

 one Californian oak is attacked by over forty different C^'nipids that 

 are never found on an}^ other oak in that region, although some of 

 them have occurred on a rare oak in southern Arizona and on an oak 

 in the Channel Islands. This is considered to afford evidence of the 

 close relationship of these local and isolated oaks. There is one 

 American oak on which no Cynipid galls have yet been found. 



