272 University of California PuUications. [Entomology 



Life-History. — The life-cycle of Hippodamia ambigua from 

 egg to adult at Berkeley, California, during April and May was 

 33.2 days. The various stages required the following periods of 

 time : egg stage, 6 days ; first larval, 3.8 days ; second larval, 4.7 

 days; third larval, 3.6 days; fourth larval, 7.3 days; and the 

 pupal stage, 8.0 days. The variations within these periods were : 

 first larval, three to five days ; second larval, four to five days ; 

 third larval, three to four days; fourth larval, six to nine days, 

 and in the pupal state, seven to nine days. 



Life-History — Hippodamia amhigua Lee. 

 Berkeley, 1913 



Average 6 3.8 4.7 3.6 7.3 8 33.2 



Feeding Habits. — The eight individuals used in the larval 

 feeding experiment were the same as those from which the life- 

 history records were secured. During the period extending over 

 approximately 28 days a maximum of 396 and a minimum of 

 269 aphids were eaten, giving an average of 312 for the period ; 

 the daily average extended from 10.3 to 14.3, with a general 

 average of 11.4 aphids per day. Of particular interest is the 

 comparatively low number consumed during the first eight or 

 nine days, and even after this the number was very low, 37 

 aphids being the largest number eaten by an individual in one 

 day. The temperature during the early part of the test was 



