~19- 
and W. E. Stone state: "Larvae of Anastrepha ludens Loew may be exposed 
to low temperatures (30° to 31° F,) for exceedingly long periods without 
immediate death resulting. Larvae showing life after exposures, however 
are not to be considered dangerous, as they appear to be fatally injured. 
No larvae exposed to low temperatures for a period exceedine 10 days 
have succeeded in developing: into puparia from which adults? endrged . 
These results are very similar to those obtained on the Mediterranean 
fruit fly and the two series of results tend therefore each to confirm 
the other." 
JAPANESE BEETLE AND ASIATIC BEETLE RESEARCH 
Grubs of Asiatic garden beetle prefer dandelion roots.--I. M. Haw— 
ley has made a study of grub population in the Chestnut Hill district 
of Pennsylvania, resulting in determination of an average of 7.8 grubs 
per square foot. He states: "It was noted last fall, as well as this 
Spring, that grubs were unusually abundant about dwarf dandelion, a 
weed common in this locality. Four diggings where this plant was gerow— 
ing yielded 67 grubs, with an average of 16.8 per square foot." 
Flooding as control for Japanese beetle.--F. E. Baker, of the 
Moorestown, N. J., laboratory, reports final observations on larvae 
which had been submerged in a cranberry bog for 150 days, the normal 
flooding period. "The results of the final observations on these larvae 
are as follows: Larvae 150 days under water, 23.0 per cent normal; 
larvae 150 days in unflooded field, 98.0 per cent normal. It is ap-— 
parent that normal flooding will not free a cranberry bog of its entire 
infestation, but it may reduce the number below that which would cause 
any appreciable damage." 
stock effective in grub control.--W. E. Fleming and F. E. Baker, Moores— 
town, report: "Two strips 1 foot wide the entire length of each of the 
sections containing young evergreens and shrubs have been dug and exam— 
ined for Japanese beetle larvae. These sections were treated with acid 
lead arsenate at various dosages in 1930 before the plants were set in 
and have been handled the same as a certified nursery block at a commer- 
cial nursery by adding sufficient lead arsenate in 1931 to bring the 
concentration of each section back to its original strength. The results 
of these surveys of 420 square feet per section are as follows: Larval 
recovery at 1,000 pounds per acre, 0; at 1,500 pounds per acre, 0; at 
2,000 pounds per acre, 0; check, 100." 
Lead arsenate treatment of soil in deciduous and evergreen nursery 
Colonies of Tiphia vernalis gain in strength.--"The entire staff 
of the parasite section at the Moorestown laboratory assisted J. W. Ba- 
lock in the recovery work on Tiphie vernalis Roh.," reports ©. H. Hadley. 
"Twenty-one colonies were scouted and ten recoveries were made; two in 
New Jersey, seven in Pennsylvania, and one at Flushing, Long Island. The 
