8 



BULLETIN 1363, U. S. DEPARTMENT OF AGRICULTURE 



The range of Compsilura and the overlapping of generations may 

 be given as follows : First generation. May 24 to July 3 (40 days) ; 

 second generation, June 24 to August 22 (59 days) : third genera- 

 tion, July 24 to October 1 (69 days) ; fourth generation, August 24 

 to November. 



For the most part it is the progeny of the second to fourth genera- 

 tions that hibernate, for it is rarely that a collection made before 

 September 1 gives Compsilura in the spring. There are exceptions, 

 however, one collection being dated August 22. 



STATUS OF SUMMER HOSTS 



During the latter part of May and the early part of June. Comp- 

 silura finds at hand a good many insects favorable for its develop- 

 ment. The flies that issue first attack the hosts then accessible, and 

 the flies that issue later attack not only those but many more. In 

 Table 3 are listed the known hosts of Compsilura, the horizontal 

 black line indicating the presence of host larvae in the field at the 

 time when they are subject to the attack of the parasite. The records 

 indicate that, although Compsilura may successfully attack early- 

 stage larva?, the intermediate stages are more acceptable. 



Table 3. — Host list of Compsilura concinnata, showing the field appearance of 

 the insects based upon the larval collections received at the gipsy-moth 

 laboratory a 



Hosts May ] June 



July ! Aug. | Sept. 



Oct. 



Nov. 



Dec. i Jan Feb. 



Mar. ; Apr. 

















! j 





Alypia octomaculata Fab- 















Ampelophaga myron 











Anisota rubicunda Fabri- 

























Anisota senatoria Smith 



i 









Anosia plexippus Linns' 



Apatela americana Harris.. 

 Apatela furcifera Guene6.__ 

































Apatela sp 











! 





Arctiid larvae 











Arsilonche albovenosa 

 Qoeze _ 













Autographa brassicae Riley 





I 1 













Basilarchia archippus 

 Cramer 



Basilarchia astyanax Fab- 

 ricius 



Oallosamia promethea 



































Calpe canadensis Bethune.. 











— 



i 













Cerura occidentalis 

 Lintner . 

















Charidryas nycteis Double- 











- 























Cirphis unipuncta Ha- 











Cnidocampa flavescens 

 Walker 













Croesus latitarsus Norton.. 















<» Period in which hosts are subject to attack; period of hibernation (indicating hibe- 



nating hosts from which Compsilura has been reared). Adults of Compsilura concinnata issue from 

 hibernating hosts April to June. 



