Vol. 1] Clausen. — Life-Histories of California Coccinellidae. 267 



Life-History — Hippodamia convergens Guer. 

 Sacrameuto, 1913 



Feeding Habits. — The larvae immediately after hatching con- 

 sume one or two aphids per day, but this number rapidly in- 

 creases until near the end of the larval stage, when fifty or more 

 may be eaten each day. There is no appreciable diminution in 

 the number eaten upon days when moulting takes place, inas- 

 much as this requires only a short time, and the larvae immedi- 

 ately afterward resume feeding very actively. Throughout the 

 experiment the hop aphis {Phorodon kumuli) was used, with the 

 exception of May 16-17, when the small rose aphis (Macro- 

 siphiim rosae) was substituted. The total number of aphids eaten 

 during the stage ranged from 232 to 487, with an average of 349 

 for twelve specimens. The daily individual averages varied from 

 17.2 to 24.2 aphids per day, with a general average of 20.7 aphids. 

 These data were compiled upon the basis of the number of days 

 intervening between hatching and pupation, even though in 

 nearly every case the larvae remained inactive and without food 

 for one or more days preceding the easting of the fourth larval 

 skin. All individuals were full size at the time of emergence with 

 the exception of No. 6, which, strangely enough, consumed the 

 largest number of aphids during the larval period. 



