70 NEW YORK STATE MUSEUM 



other lines. Some of these inA'estigations gave results which 

 appear to have a positive value, while others only proved cer- 

 tain measures comparatively useless. 



Destroying the pupae. Our finding the pupae of this insect 

 within three inches of the surface of the soil and their great 

 delicacy led Mr Barden to suggest that a certain field be culti- 

 vated at a time when the majority of the insects were in the 

 pupal stage. The earth was plowed away from the vines and 

 then turned back, care being taken to get as close to the roots 

 as possible. Investigations in this field in the early part of 

 June resulting in finding from 50 to 60 grubs about many of the 

 vines, while repeated search the latter part of the same montli 

 failed to uncover more than three or four insects about a vine 

 and in many cases not a specimen was found. It was too early 

 for the insects to emerge and destruction by cultivation appears 

 to be the most reasonable if not the only way of accountings 

 for their disappearance. This, taken in connection with the 

 great care necessary in handling the pupae, leads us to believe 

 that much can be accomplished by so planning cultural opera- 

 tions that the vinevards will be horse-hoed at the time when the 

 majority of the insects are in the pupa or " turtle " stage. Jt 

 has been shown on a preceding page that a difference of a week 

 or more may exist in the development of the insect in vineyards 

 within a few miles of each other, and this is probably true of 

 localities even nearer each other. The insects being in the 

 earth are affected by its character and in a warm, light soil 

 emerge earlier than in a heavy one. This difference in the 

 period when the beetles appear renders it necessary for each 

 vineyardist to keep watch of the development of the insects on 

 his own grounds, and plan to do his cultivating at the most 

 favorable time. The pupal stage, as determined by careful 

 experiments, lasts about two weeks, and as the emergence of 

 the beetles extends over a considerable period, it is suggested 

 that the cultivation be delayed till a few of the very early 

 beetles are nearly ready to emerge from the soil. No very 

 serious injury will result if a few actually forsake their pupal 



