274 University of California Publications. LExtomolo(it 



Adult Feeding Records — Hippodamia amhigua Lee. 



Average 26.1 27.8 26.2 28.3 26.6 24.7 28.6 24.7 24.7 26.9 



011a abdominalis Say 



This species is one of the most important aphid eaters in 

 California, and is especially abundant in the southern part of 

 the state. Feeding has been observed upon the hop, rose, melon, 

 and cabbage aphids, but a very decided preference is usually 

 shown for the walnut aphis {Clirornaphis juglandicola) . The 

 adults hibernate singly under fragments of bark, dead leaves, 

 etc., and emerge in the spring somewhat later than Hippodamia 

 convergens. 



Oviposition. — The time intervening between emergence and 

 mating was found to average 1.7 days, with a range of one to 

 three days. From mating to egg-laying, the time varied from 

 seven to ten days, with an average of 8.6 days for the nine indi- 

 viduals under observation. 



The period of oviposition ranged from 19 to 47 days, with an 

 average of 34.7 days. The proportion of days upon which ovi- 

 position occurred was 73.8 per cent as a maximum and 66 per 

 cent as a minimum, and averaged 70.3 per cent. The maximum 

 number of eggs deposited in one day was 25 and for the full 

 period of oviposition 298, with averages of 6.3 and 294 respect- 



