GRAPEVINE FLEA-BEETLES. 



15 



DURATION OF FIRST LARVAL STAGE. 



The duration of the first stage, of 74 larvae reared, varied from 3 

 to 9 days with an average of 6.16 days, as shown in Table XIV. 



Table XIV. — First larval 

 stage of A . woodsi, North 

 East, Pa., 1916. 



Table XV. — Second larval 

 stage of A . woodsi, North 

 East, Pa., 1916. 



Number of 



Duration 



larvae. 



of stage. 





Days. 



1 



3 



1 



4 



17 



5 



32 



6 



16 



7 



3 



8 



4 



9 



174 



2 6.16 



Number of 



Duration 



larvae. 



of stage. 





Days. 



4 



4 



18 



5 



15 



6 



11 



7 



14 



8 



2 



10 



1 



15 



165 



2 6. 46 



1 Total. 



2 Weighted average. 



i Total. 



2 Weighted average. 



The records in this stage cover a period from June 18, the earliest 

 recorded date of hatching, to July 15, the latest recorded date of 

 passing the first molt. 



DURATION OF THE SECOND LARVAL STAGE. 



The duration of the second larval stage varied from 4 to 15 days 



with an average of 6.46 days, as shown in Table XV. The total 



period covered by records on larva? of 

 Table XVI. — Feeding period of ,-,• , ± j j r t nr ± 



third larval stage of A woodsi, ' thls sta S e extended from June 25 to 



North East, Pa., 1916. July 21. 



DURATION OF FEEDING PERIOD OF THIRD LARVAL 

 STAGE, NORTH EAST, PA., 1916. 



The duration of the feeding period of 

 the third stage of 41 larvae varied from 3 

 to 13 days, with an average of 6.51 days, 

 as shown in Table XVI. The total period 

 covered by records of larvae in this stage 

 extended from July 1 to 26. 



DURATION OF PERIOD IN GROUND. 



Number of 



Duration 



larvae. 



of period. 





Days. 



2 



3 



2 



4 



9 



5 



12 



6 



7 



7 



1 



8 



4 



9 



3 



10 



1 



13 



141 



2 6.51 



i Total. 



2 Weighted average. 



The period in the ground includes the 

 prepupal period, which is the latter part 

 of the third stage, the pupal period, and the early part of the adult 

 stage before emergence from the pupal cell. Fifty-three individuals 

 were carried through this period. The minimum time required 

 was 14 days, the maximum 21 days, and the average of 16.15 

 days. The period covered by these records extended from July 7, 

 when the first larva entered the ground, until August 29. when the 

 last adult emerged. These data are given in full in Table XVII. 



