50 DECIDUOUS FEUIT INSECTS AND INSECTICIDES. 



page 78, presents figures and a full description, with interesting 

 observations on its feeding habits, etc. He records having bred the 

 moth the year previous from the *' black-knot "' of plum, from the 

 cockscomb-like hollow gall {ulmicola Fitch) on the leaf of an elm, 

 which is produced and inhabited by aphides, and also from a sessile 

 hollow gall about the size and shape of a large pea or small cherry on 

 the leaf of red oak {Quercus riibi'a) and described by Mr. Bassett as 

 Quercus singularis. 



The rearing of moths from larvse in curculio-infested plums and 

 " black-knot '' and from elm and oak galls led Mr. Walsh to surmise 

 that the larvae did not infest sound plums and " black-knots," but fol- 

 lowed the injury caused by the curculio, and in the elm and oak galls 

 he believed the larvae to be guests, it being uncertain whether the}^ fed 

 upon the tissues of the gall, upon the gall insects, or, in the case of the 

 elm leaf gall, upon the sugary dust secreted by the aphides. Glover, 

 in his report us Entomologist of the United States Department of 

 Agriculture for 1867, page 73, briefly refers to Mr. Walsh's discovery, 

 adding nothing, however, in the way of personal observations. 



In Riley's First Missouri Report, page 65 (1869), brief reference 

 is made to the plum moth in connection with a consideration of the 

 plum-feeding habits of the codling moth, and again in the Third 

 Report, page 6 (1871), it is mentioned as feeding on apples as they 

 mature. Later in the same report (p. 25), under the caption "Two 

 true parasites of the plum curculio," Doctor Riley points out 

 Walsh's error in supposing that Sigalphus citrcidionis Fitch was not 

 a parasite of the plum curculio, but of his plum moth, adding that 

 this last insect had been bred by him from galls {Quercus frondosa 

 Bassett), from haws, from crab apples, and abundantly from culti- 

 vated apples. In a footnote to an article on the codling moth in his 

 Fifth Report, page 5 (1873), Riley comments further on this species 

 as follows : " There is another and smaller w^orm, namely, the larva 

 of what Mr. Walsh called the plum moth {Semasia prunivora Walsh), 

 which is quite connnon on haws and apples. It does not penetrate 

 deeply into the apple, but remains around the calyx and generally 

 spins up there, and it so closely resembles the young apple worm that 

 the two might be easily confounded." In the American Entomolo- 

 gist for 1880, page 131, in an article on parasites of the plum curculio, 

 Doctor Riley quotes from his previous article on this subject in his 

 Third Report, page 25. 



The species is next mentioned in economic literature by James 

 Fletcher in his report as Entomologist and Botanist to the Central 

 Experimental Farm (Canada) for 181)(), page 261, where he records 

 that in Victoria, B. C, in 1895, specimens of a small caterpillar were 

 found feeding on the surface of the fruit of the apple, particularly 

 at the calyx end, eating the skin and mining a short distance beneath 



