December, '10] 



TITUS: ALFALFA LEAF-WEEVIL 

 TABLE 11 



467 



Final totals and averages 



Totals 



1909-10 . . . 



190 



355 



395 



2466 



1.81 



2.07 



6.24 



12.98 



Notes on Stages 



Egg: The egg is oval, rounded at the ends and when first deposited 

 is lemon-yellow in color, 0.55 mm. to 0.65 mm. long and 0.32 mm. to 

 0.38 mm. wide. Two to four days after being laid, a dark spot appears 

 at one end and as incubation progresses, this spot enlarges, the egg 

 becoming somewhat paler on the other portions. Under the micro- 

 scope the surface of the egg appears very slightly roughened and 

 sculptured with hexagonal depressions. At one end this hexagonal 

 sculpturing is somewhat drawn out until it appears like striae. The 

 incubation period varies from seven to sixteen days, having an aver- 

 age of about ten days. 



Hatching Record 



Table 12 shows period of incubation for 1139 eggs taken at different 

 periods during 1909 and 1910. 



