24 NEW YORK STATE MUSEUM 



recently hatched grubs were placed on the surface of the soil 

 in the 4 inch vertical portion. One grub had made its way 

 through the entire mass of soil by July 31, another by Aug. 1, 

 and 11 others by the 3d, making a total of 13 which had traveled 

 the whole length of this tube in a period of four days. 



Another £ inch tube, 10 inches long with 3| inches vertical and 

 6^ inches of its length horizontal was similarly packed and 13 

 grubs placed on the surface of the soil July 29. Four of these 

 had made their way throughout the entire length of the tube by 

 Aug. 3. Another tube 12 inches long, \ inch in diameter, with 

 2\ inches of its length vertical and the remainder horizontal was 

 filled with tightly packed soil and a number of grubs placed in 

 it Aug. 1. On the 7th one grub had made its way through 1\ 

 inches of this tightly packed material. It would seem from the 

 above experiments that, Avhile a great many grubs undoubtedly 

 perish in making their way from the vine to the succulent roots 

 on which they feed, they are capable of overcoming great 

 obstacles, and the facts ascertained above at least raise a ques- 

 tion as to the advisability of attempting to interpose barriers 

 between the grub and the roots on which it feeds. 



The young larvae or grubs are undoubtedly able to exist for 

 some time without food. They soon make their way when pos- 

 sible to the young feeding roots, where they may sometimes be 

 found in considerable numbers. The writer, in the middle of 

 August 1902, succeeded in finding eight of these little creatures 

 under a small bunch of feeding roots. They were less than one 

 quarter grown, and under larger roots near them several others 

 were found which were about half grown. Aug. 18, 1903, quarter 

 and nearly full grown grubs were found in some Westfield vine- 

 yards. The occurrence of few half grown larvae and of con- 

 siderable numbers of nearly full grown individuals the middle of 

 September 1902 indicates that these creatures develop very 

 rapidly after they have found suitable roots on which to feed. 

 The finding of a small grub scarcely J^ inch long July 2 shows 

 that some do not attain their full growth in the fall, since this 

 individual could not have hatched from an egg laid in 1902, as 

 the beetles had hardly begun to appear, and that such individuals 

 must feed to some extent in the spring. It seems probable that 

 these very small grubs produce the later emerging beetles and are 



