290 University of California Puhlications. [ExToxioLociY 



Egg-Laying Records — Cyeloneda sanguinea Linn. — (Continued) 

 Berkeley, 1913 



Average 7.8 6.4 7.2 6.0 7.5 5.2 6.4 6.5 8.1 6.7 



Life-History. — In the following table is given the results of 

 two series of life-history experiments, the results of which are 

 quite noticeable in their difference. The eggs for the first set, 

 of which three survived, were secured May 1 and hatched six 

 days later. The first larval period varied in length from five to 

 six days, the second from four to nine days, the third from three 

 to five days, the fourth from five to eight days, and the pupal 

 period from five to seven days. It will be noted that the varia- 

 tion in the second and fourth stages was very great, but the in- 

 verse ratio seemed to exist in the remaining stages, so that the 

 complete life cycles for the three individuals varied only two 

 days. In the remaining cases the egg stage required only five 

 days, the first larval period a constant four days, the second 

 period two to three days, the third period two to three days, the 

 fourth period three to five days, and the pupal period three to 

 four days, giving a total of from 20 to 23 days, as compared with 

 33 to 35 days with those reared seven weeks previously. The 

 difference in mean temperatures at the time of the two series of 

 experiments was approximately 10° F. 



