CONTROL OF ^[EALYBUGS 



Table 1. Ovipositiox of Cryptolaemus AIontrouzieri at Constant 

 Temperatures. Waltham, Mass., 1935 and 1937. 



193: 



1937. 



*TemiJerature fluctuated consnderably, especially during some adjustments of 

 the controls, and was higher than 60° F. at times. 



Incubation of Eggs 



The incubation period was determined from observations of eggs placed 

 in glass tubes partially filled with plaster of Paris and resting on moist 

 sand in petri dishes (11). This method has frequently been used with 

 satisfactory results, and the fact that larvae hatched from not more than 

 50 percent of the eggs was apparently due to minor injuries resulting 

 from handling and making observations. 



Table 2. Incubation of Eggs of Cryptolaemus Montrouzieri at 

 Constant Temperatures. Waltham, Mass., 1934, 1935, and 1937. 



Number Incubation Period, Days Percent 



Year Temperature of of Larvae 



Eggs Maximum Minimum Average Hatched 



r60° F. 

 ^ 70° F. 



1934. 



80° F. 



i 



60° F. 



1935 ^ 70° F. 



80° F. 



60° F. 



1937 ^ 70° F. 



80° F. 



From the records of nearly 900 eggs presented in Table 2, it is apparent 

 that temperatures between 70° and 80° F. are most favorable for the in- 

 cubation of eggs. At a constant temperature of 80° F., the incubation 



