10 



BULLETIN 847, U. S. DEPARTMENT OF AGRICULTURE. 



period for the year covering 58 clays. It is not unusual to find un- 

 hatched eggs in the field in the latitude of West Virginia from Au- 

 gust 10 to 15, although none have been found after August 15. From 

 these and from considerable other data obtained, it appears that nor- 

 mally egg laying continues in a given locality from 50 to 60 days, 

 although perhaps no single individual oviposits over so long a period 

 of time. 



INDIVIDUAL EGG CAPACITY. 



The number of eggs normally deposited by a single female beetle 

 is not great, the average number having been found by different in- 

 vestigatory to vary considerably. Felt and Joutel (6) mention 10 

 as being about the quota for one individual, while Becker (14), mak- 

 ing observations in the Ozark Mountain regions, found the number 

 to range from 16 to 93, with an average of 40.8 per female for five 

 individuals. The writer obtained egg counts from 15 individuals, 

 the figures being shown in Table II. 



Table II. — Individual eyg capacity of female beetles of the roundlieaded apple- 

 tree borer at French Creek, W. Ya. 



« 



Year. 



Xumber 



of 

 females. 



Average 



of eggs. of p e Jf 

 female. 



1911 



3 

 1 



1 

 1 



1 

 1 



7 



52 

 17 

 20 

 22 

 13 



17.3 



1914 



17 



1914 



20 



1914 



22 



1912 



13 



1912 



20 20 

 193 | 27.6 



1914 •- 









Total 



15 



337 









Average number of eggs per beetle 22, 5 



Table II shows that the minimum and maximum numbers of eggs 

 obtained from 15 beetles were 13 and 27.6, the average being 22.5. 

 Since these records were obtained in several different years under 

 conditions that were approximately normal they probably represent 

 fairly accurately the average number of eggs laid by females in the 

 locality mentioned. 



PERIOD OF INCUBATION OF EGGS. 



The time required for the eggs to hatch has been variously stated 

 at from 8 days to 3 weeks. The writer noted the period in 8 in- 

 stances, the data for which are set forth in Table III. 



