14 



BULLETIN 901, U. S. DEPARTMENT OF AGRICULTURE. 



Table XII. — Incubation period of A. 

 woodsi, North East, Pa., 1916. 



Date of 



Date of 



Number 



Duration 



tion. 



hatching. 



of eggs. 



of period. 









Dai/s. 



June 10 



June 23 



2 



13 



10 



25 



i 



15 



10 



26 



2 



16 



10 



27 



1 



17 



15 



27 



2 



12 



15 



28 



3 



13 



15 



30 







15 



25 



July 7 



9 



12 



26 





12 



11 



M0 



= 12.82 



i Total. 



Weighted average. 



On leaves of the Concord grape and similar varieties the larva 

 feeds on the upper surface, leaving narrow, irregular, chainlike feed- 

 ing marks, much narrower and less continuous than those of the 



larger species. On these varie- 

 ties there is also a great tendency 

 for the larva to feed on leaf veins 

 and in the flower cluster. 



Its manner of passing the 

 pupal period and its relation to 

 temperature are very similar to 

 those of the larger species. 



LIFE HISTORY. 



EMERGENCE FROM HIBERNATION AND 

 OVIPOSITION IN 1916. 



Adults were first noted in 1916 

 on May 29 and appeared in abun- 

 dance at that time. Beetles 

 were copulating on the day when first observed and this was con- 

 tinued intermittently as long as beetles of this generation were found 

 on the vines. Oviposition was first noted on June 6 and continued 

 until after the middle of July. 



INCUBATION. 



The incubation of eggs recorded in 1916 required from 11 to 17 

 days with an average of 12.82 days, as shown in Table XII. 



TIME AND DURATION OF THE LARVAL FEEDING PERIOD OF ALTICA WOODSI, NORTH 



EAST, PA., 3916. 



Forty-one larvae were carried through the larval feeding period 

 from the date of their hatching to the date of their entering the 

 ground. The duration of this period varied from 13 to 27 days, with 

 an average of 18.71 days. The period covered by records on feeding 

 larvae extended from June 18 to July 26. Complete data on the time 

 and duration of this period are given in Table XIII. 



Table XIII. — Time and duration of larval feeding period of A. woodsi, North East, 



Pa., 1916. 



Date of 



Date of 

 entering 

 ground. 



Number of 



Duration 



Date of 



Date of 

 entering 

 ground. 



Number of 



Duration 



hatching. 



larva. 



of period. 



hatching. 



larvae. 



of period. 









Days. 









Days. 



June 18 



July 7 



1 



19 



June 26 



July 15 



1 



19 



18 



10 



1 



22 



28 



21 



2 



23 



20 



10 



2 



20 



29 



15 



4 



16 



21 



10 



1 



19 



30 



18 



1 



18 



22 



19 



1 



27 



30 



24 



1 



24 



23 



10 



5 



17 



July 1 



24 



1 



23 



23 



12 



1 



19 



4 



17 



1 



13 



24 



10 



3 



16 



4 



21 



4 



17 



24 



12 



1 



18 



8 



21 



2 



13 



25 



17 



5 



22 



8 



26 



1 



18 



25 

 26 



18 

 14 



1 

 1 



23 



18 















l 41 



2 18. 71 



i Total. 



2 Weighted average. 



