282 Vniversity of California Publications. [Entomology 



Life-History. — All individuals used in the life-history experi- 

 ments were secured from a single cluster of eggs deposited May 

 26. These hatched five days later, and reached the adult stage in 

 aj)proximately twenty-six days, the larval and pupal stages re- 

 quiring twenty-one and five days, respectively. The first larval 

 stage required from four to six days, the second three to six days, 

 the third three to five days, the fourth six to eight days, and 

 the pupal period a constant five days with a single exception, 

 which required six days. No striking deviations from the normal 

 can be noted here, and the range of from twenty-nine to thirty- 

 two days in the total period represents only a comparatively 

 slight variation for a life-cycle of that length. 



Feeding Records. — The larval feeding records were secured 

 from ten individuals fed throughout the period upon medium- 

 sized rose aphids. The number eaten varied from 299 to 349 for 

 the period of approximately 25 days, with an average of 326 

 aphids. The daily average for all specimens was 11.2, repre- 

 senting a range of from 15.3 to 19.3 aphids per day. Feeding 

 was continuous up to the day of pupation. 



The adult individual records for the fifteen-day period varied 

 from 589 to 672, and averaged 624, which is very uniform as 

 compared with the variation secured in experiments with other 

 species. The daily records as derived from this ranged from 

 39.2 to 44.8, with an average of 41.6 aphids per day. The largest 

 number eaten in one day by a single adult was 77 aphids. 



Medium-sized rose aphids {Macrosiphum rosae) were used 

 exclusively for feeding purposes in this experiment. 



Larval Feeding Records — OUa oculata Fabr. 

 Eiverside, 1914 



