Vol. 1] Clausen. — Life-Histories of California Coecinellidae. 259 



spring, and in several eases observed has done good work in the 

 control of the rose aphis. 



Oviposit ion. — No records were secured of the time interven- 

 ing between emergence, mating, and egg-laying. The period of 

 oviposition extended in one case over 42 days, while the average 

 for ten specimens was 29.2 days. During the period the propor- 

 tion of days upon which oviposition occurred ranged from 66.6 

 to 78.1 per cent, with a general average of 75.0 per cent, which 

 indicates a quite general uniformity in this respect. The maxi- 

 mum number of eggs deposited by an adult was 369, the minimum 

 109, and the average 249 eggs ; the maximum number deposited in 

 one day was 31, while the average for all individuals was 8.4, with 

 a range of from 4.7 eggs to 10.4 per day. It will be observed 

 from the following table that the individuals depositing the larg- 

 est number of eggs, as a general rule also gave the highest daily 

 record. 



Egg-Laying Records — CoccineUa trifasciata Linn. 

 Berkeley, 1914 



Date 



Apr. 18 



19 



20 



21 



22 



23 



24 



25 



26 



27 



28 



29 



30 



May 1 



2 



3 



4 



5 



6 



7 



8 



9 



10 



11 



12 



13 



