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jin the fallow soil only 16.5 percent were in the upper 5 inches and 
greatest numbers were near the bottom of the bin. Thirty-five of the 
79 grubs recovered were below the 9-inch level. In the bin with grass 
17 grubs had changed to the prepupal condition, but none in the fal-— 
low bin had made this change." 
TRUCK CROP AND GARDEN INSECTS 
Winter kill of beet leafhopper correlates with fat content of bod- 
ies.--J. C, Chamberlin, D. E. Fox, and R. A. Fulton, Twin Falls, Idaho, 
report: "The fat determinations (of Eutettix tenellus Bak.) made in con— 
nection with the February set of hibernation cages show an interesting 
correlation with winter kill. In every instance this past winter mortal-— 
ity as shown by cage recovery is paralleled by positive corresponding 
variation in fat content. Thus in the present series of cages, the in- 
sects from Castleford plot showed the lowest fat content, with a determi- 
nation of 25.4 percent; Burley was next, with 25.9 percent; Wendell next, 
with 26.7 percent; and Twin Falls highest, with 27.5 percent. This is 
the same as the order of cage recovery (Castleford, 0.5 percent; Burley, 
0.8 percent; Wendell, 3.5 percent; and Twin Falls, 17.0 percent) * * * 
These determinations (Twin Falls) compare with 34.0 percent on February 
17, 1932. It is interesting to note that these are the lowest records 
that have thus far been made on overwintering females in the Twin Falls 
area. The determinations throughout the current winter, as for 1931-32, 
show that a drop in fat content follows a sudden drop in temperature.” 
Control of cyclamen mite and broad mite.--Reporting further on 
his study of Tarsonemus pallidus Bks. and T. latus Bks. (see Monthly 
Letter, October and November 1932), F. F. Smith, Washington, D. C., says: 
"Fumigation tests with naphthalene or calcium cyanide have shown that 
the broad mite is more readily killed than are the exposed cyclamen 
mites. * * * in some cases at least that there has been a confusion of 
the species of mites concerned. As the cyclamen mite is so well pro— 
tected by its position on the plant, it is evident that once established 
it is not readily destroyed. * * * One of the heat treatments, either 
immersion in hot water for 15 minutes at a temperature of 110° F. or 
exposure for 30 minutes at the same temperature in saturated atmosphere 
(vapor heat), appears to be the most successful. * * * Mites beneath 
the sepals and petals on buds have been killed by either treatment and 
the flowers opened without further injury. * * * The plants must be 
kept shaded with newspapers for 24 to 48 hours following treatment to 
prevent foliage injury. Most of the host plants that have been tested 
are tolerant of this treatment; snapdragons and begonias are moderately 
injured; and tips of chrysanthemums are sometimes slightly injured, but 
new growth develops later on these plants." 
Molasses-derris extract spray fatal to gladiolus thrips.—-H. H. . 
Richardson, of the greenhouse insects laboratory, Washington, D. C., re— 
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