SAL 
High mortality rate of Eutettix tenellus indicated by fat 
studies.--R. A. Fulton, Twin Falls, reports that during November beet 
leafhoppers forced from Russian thistle to sage have shown a progres— 
sive decrease cf 20 to 15 percent in total fat; the last determine- 
tion, 25.6 percent, on December 10, being lower than determinations 
for 1931 and 1932 on the same date. This indicates the probability 
of a high nortality rate from starvation, provided the nresent 
drought continues. Newly germinated mustard plants have been found 
to carry very little food value, as reflected by the inability of 
leafhoppers feeding thereon tu accumulate a reserve of glycerides. 
Germination of mustards after this date would probably change the 
total fat ccntent very little. These determinations indicate the 
probability of a high winter nortality rate because cf deficient re- 
serve food supply. 
tures.--F. H. Harries, Twin Falls, in studies on the duration of the 
egg period cf E. tenellus having possible field application in the 
estimation of the date of migration, has conducted two tests in 
which direct temperature summations have been compared with the 
thermal constant indicated by constant-temperature data. In the 
first test, eges were deposited during a 12-hour period at 90° F., 
were then transferred to the insectary at varyiny temperatures for 6 
days, and were finally allowed to hatch at 90° F. The mean time 
spent at 90° F. was 5.91 days, or 122.38 effective day-degrees. The 
temperature accumulation during 6 days in the insectary was 72.17 
day-degrees, or a total of 194.55 day-degrees, which a»nproaches 
rather closely the theoretical thermal constant of 196 day-degrees. 
In the second test, under somewhat different temperature conditions, 
the accunulaticn was 188 day-degrees, conipared with the theoretical 
thermal constant of 196 and determined on the basis cf constant tem-— 
peratures. Daily alternations of temperatures have indicated some 
acceleration of development over the constunt temperature results, 
though it is doubtful if these differences are large encugh to pe of 
b 
Duration of egg period of EB. tenellus uncer various tempera- 
H 
> 
importance in field work. Studies on the rate of oviposition at dif- 
ferent relative humidities indicate that relative humidity between 20 
and 90 percent at 90° F. prcbably has no effect on the rate of egg- 
laying. 
Action of dusts and sprays against Mexican bean bectle in New 
Mexico.--J. R. Douglass, Estancia, N. Mex., summarizes as follows the 
action of various sprays and dusts against Epilachns corrupta Muls.: 
"in the dusting tests derris led in the percentaze killed, followed 
in order by Cubor dust, zine arsenite, calcium srseuate (Corons), 
sodium fluosilicate, cryclite, calcium arsenate (Niagara), calcium 
arsenate (Dow), magnesium arsenate, leud arsenate, and barium fluo- 
Silicate; whereas in the spraying.tests zinc arsenite led in the per- 
centage killed, followed in order by calcium arsenate (Corona), mag- 
