CODLING MOTH IN SANTA CLARA VALLEY. 127 



Table XII.- — First-brood eggs. Incubation period of eggs laid in rearing cages — Contd. 



In all 897 eggs wore deposited and 720 hatched, or slightly over 80 

 per cent. The maximum length of the egg stage was 17 days, the 

 minimum 8, and the average 12.4 days. (See Table XIII.) The red 

 ring appeared after from 1 to 8 days but averaged from 2 to 5 days. 

 The black spot appeared from 6 to 15 days after the eggs were 

 deposited but usually appeared after 8 to 9 days. 



An examination of Table XII shows that after the first lot of eggs 

 had been deposited the length of the egg stage was fairly constant 

 throughout the oviposition period of the spring moths. As has been 

 observed by other writers, eggs which were deposited on the same 

 day sometimes varied from one to three days in the length of the egg 

 stage. This was due to differences in embryological development of 

 the eggs within the body of the female. 



Table XIII. — Incubation period of first-brood eggs . Summary of Table XII. 



A summary of the incubation periods for the total number of eggs 

 deposited by the spring-brood moths is shown in Table XIV. 



