12 



SUMMARY OF LIFE HISTORY. 



As a rule, there are eight molts after the egg stage, although occa- 

 sional males molt only seven times. The entire period from the egg 

 stage to the adult averaged 295.3 days for 19 individuals. 11 of which 

 were males averaging 281 days with a variation. of 233 to 321 days. 

 and 7 females averaging 321 days, with a variation of 291 to 397 

 days. About a year is required for the full development of a 

 generation. 



The duration of the different instars is shown in the accompanying 



table: 



Duration of instars of changas reared from the egg. 



The preoviposition period of adult females is long. Three indi- 

 viduals averaged 79 days between the time of becoming adult and 

 the first egg laying, 62 days being the shortest time and 93 the 

 longest for this period. 



That adults may live several months under favorable circum- 

 stances was shown by tests made with adults placed in battery jars 

 filled with earth and provided with ample vegetable food. The 

 longest adult life recorded was of a male which was eaten by a 

 female 160 days after the final molt. An adult female taken in 

 the field died a natural death after being kept alive for 127 days. 



The numerical proportion of males to females bred in captivity 

 was about equal, and the same is true of captures made in the field. 

 Individuals have been brought to the adult stage every month of 

 the year in the insectary, but there seems to be a fairly well-defined 

 preponderance of final molts during the fall months. It is possible, 

 therefore, that the flight to lights so marked during October, Novem- 

 ber, and December is in part at least a nuptial flight. All stages may 

 be found in the field at any time of the year. 



EGG STAGE. 



The newly egg is gray in color and oblong-oval in shape, with 

 a shiny, unsculptured surface (PL III, fig. 1), measuring about 3 

 millimeters long and 1.7 millimeters wide. The egg increases con- 



