24 BULLETIN 1363, U. S. DEPARTMENT OF AGRICULTURE 



PAPILIONIDAE 



The species Papilio polyxenes Fab. and Papilio troilus L. have 

 been discussed elsewhere in this bulletin. Papilio tumus L., a 

 species similar in habit to the others of its genus, has given Comp- 

 silura frequently. It is very probable that the future will show 

 this species to be of the same host value as its relatives. 



PIERIDAE 



The cabbage worm (Pontia rapae L.) is nearly always to be found 

 in abundance in some locality or other. It hibernates in the chry- 

 salid stage. It is an acceptable host and, because of its abundance 

 and wide distribution, possesses a certain attractiveness. In 1910, 

 Tothill (7, p. 223) succeeded in rearing a great many flies and, in 

 some instances, a total of 40 per cent parasitism was obtained. Some 

 years later, Culver, 17 who had received large collections of this ma- 

 terial for life-history work, recorded a fair amount of parasitism, 

 but in no case did he equal the record of the former investigator. 

 In contrast to these records, however, the data obtained by the 

 writers show but little parasitism. 



. SATURNIIDAE 



Cdllosamia promethea Dru., Telea polyphemus Cramer, Sarnm 

 cecropia L., Automeris io Fab., and Hemileuca maia Dru. are five 

 species of doubtful host value. From the last-named Compsilura has 

 been reared occasionally, but considering the hundreds of larva? of 

 all stages used in the experiments, the host value of this insect is 

 insignificant. 



As has been previously stated, the value of Callosamia promethea 

 Dru. as a winter host for Compsilura appears to be negligible. Its 

 status as a summer host is apparently much more important. Since 

 Culver 1S found, while experimenting with this species and Comp- 

 silura, that he could readily obtain larviposition and successfully 

 rear adults when using early-stage caterpillars, there seems little 

 doubt that were large collections of early-stage larva? received, a 

 fair amount of parasitism would be recorded. 



The collections of Telea polyphemus Cram, have nearly always been 

 made in the pupal stage and no Compsilura were recovered from 

 them. It is sufficient to say that, in three separate collections of one 

 larva each, there were obtained two Compsilura from one of them. 



Samia cecropia L. seems to have about the same host status as T. 

 polyphemus. The material when collected as cocoons has never given 

 Compsilura. Larval collections, however, show better results. A 

 single instance of the rearing of four flies from nine third-stage and 

 fourth-stage larvae is recorded. 



Automeris io Fab. has a greater host value than any of the satur- 

 niids mentioned. Although none of the collections received prior to 

 1922 has given Compsilura, the recoveries made that year were grati- 

 fying. Furthermore, all of the material was from New York, at 

 points well outside the gipsy-moth area. From these records there 



17 Gipsy Moth Laboratory Records, 1917-18. 



