316 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 6 



posed to the poison upon the fohage except in those cases where it 

 may feed to a slight extent after leaving the old mine. 



In connection with the study of the development and habits of 

 the miner, the writer has had an opportunity of noting the effective 

 work of i^arasites. During the summer and fall various hymenop- 

 terous parasites were exceedingly abundant, so numerous in fact 

 that only a very small percentage of each brood of miners succeeded 

 in maturing. The majority of the miners are killed by small para- 

 sites when the mine is yet in the blotch stage, while many more are 

 destroyed by other species of parasites after the mine takes on the 

 mature condition. With the help of these various species of parasites 

 there will probably never be any occasion for fruit growers to fear 

 this miner. The various species of parasites reared from the mines 

 of this caterpillar are now being studied by Prof. C. R. Crosby. 



A NOTE ON TWO ELM LEAF APHIDES ^ 



By Edith M. Patch 



During the past few weeks several items concerning Elm leaf aphides 

 which have come to my notice have interested me enough so that I 

 venture to present them here, not as a formal paper, but merely to 

 call attention to the fact that two perfectly distinct and easily distin- 

 guishable species causing elm leaf curl are present in the United States. 



One of these migrates to Pyrus and Crataegus where it is known as 

 the woolly aphid of the apple and that this species extends from the 

 Atlantic to the Pacific coast nurserjanen and apple growers almost 

 everywhere can testify to their sorrow. 



A second elm leaf species, which is present in California and else- 

 where in the Pacific states, appears to be identical with a species 

 recorded from England, Germany, Sweden, and elsewhere which has 

 been ascertained by European workers to migrate from Ulmus to Rihes 

 and is at present known as idmi {jodiens) of Europe. 



These two species can readily be distinguished by their antennse. 

 The Ulrnus-Ribes species is characterized both in the spring and fall 

 migrants by having joints V and VI without annular sensoria and the 

 terminal sensorium of V is circular and fringed; the terminal sensorium 

 of VI though somewhat irregular in shape being also fringed. The 

 Ulmus-Pyrus species has typically annular sensoria on both V and VI 

 in the fall migrant and on V in the spring migrant, while in both forms 

 the circular sensorium of V is lacking, the terminal sensorium being 



iPapers from the IMaine Agricultural Experiment Station: Entomology No. 60. 



