296 University of California PuhUcatioHs. [Entomology 



than any other. In the second larval stage the variation was 

 from 2.3 to 4.7 days, and no special differences are noticeable be- 

 tween the various genera. The third stage required a minimum of 

 2.3 days for Hippodamia convergens and a maximum of 4.2 days 

 in the ease of OUa oculata. Cocci )iella and Hippodamia required 

 from 6.0 to 7.4 days for the fourth larval stage, as compared with 

 4.7 to 5.6 for the other genera, except for OUa oculata, which 

 covered 7.0 days. The pupal stage required the longest time 

 with Hippodamia, the average being 7.5 and 8.0 days, respect- 

 ively, for the two species. The variation for the remaining species 

 was from 3.5 to 6.0 days in the cases of 0. oculata and Adalia 

 hipu nctata, respectively. 



The complete life-cycle from egg to adult varied from 21.0 

 days in the case of OUa ahdomiualis to 33.2 days for Hippodamia 

 amihigua. Strangely enough, the period lengths up to and in- 

 cluding the third larval stage were approximately equal in all 

 the species, but a very considerable range was presented in the 

 fourth larval stage and pupal stage, resulting in the consider- 

 able difference between species as noted above. As stated previ- 

 ously, however, the possibility is very strong that this was, in 

 part at least, due to the varying conditions under which the in- 

 vestigations were conducted. 



Egg 

 Number stage, 

 specimens days 



C. californica 1.3 5.4 



C. trifaseiata 12 6.0 



H. convergens 8 .5.0 



H. ambigiia 10 5.5 



O. abdoininalis 14 4.2 



O. oculata 11 5.0 



A. bipunetata 7 5.0 



C. sanguinea 10 5.3 



Larval Feeding Records. — Individual feeding records were 

 secured for the entire larval period for the different species in 

 numbers i-anging from eight for Hippodamia anihigua to four- 

 teen for OUa ahdominalis. In the case of each species, enough 

 tests were started to secure approximately ten complete records 

 making due allowance for the possible mortality during the 

 larval period. In the following tabulation the length of the 



