Camphor scale controlled by_oil sprays.-—-"The analysis of the re— 
sults of the labora raves and field sprays applied in Janvary against 
seudeonidig duplex Ckll. by L. H. Dawsey, J. 0. Dumestre, L. T. Kes- 
sels, and A and A. W. Cressman have been completed and are submitted by them." 
They report that "the scales in the laboratory sprays were in the pink 
and early-gravid stage, while the scales in the field were more ad~ 
vanced, most of them being reproducing. * * * From these two series 
of tests in conjunction with the sprays applied last summer we may 
conclude: (1) The relation between efficiency of a spray and oil de— 
posited on Ae plant surface was a curvilinear one, the increase in 
mortelity being more rapid with smaller amounts of ois but the effeo- 
tiveness was still increasing when 21 x 10-5 gm. oil/cm? cf oil were 
retained by the plant surface; (2) the severity of infestation is an 
important factor in control of the cam paey scale. More oil was required 
to kill the Sadar as the population density increased; (3) the scales 
showed decreasing susceptibility to Rin as they became older. This 
applied not ok to different instars, but throughout the adult stage; 
(4) 21 x 10-5 gm. oil/cm2 of a highly refined oil did not injure cam— 
phor trees when applied as a winter spray; (5) the amount of oil depos-— 
ited on a sprayed plant can be increased by decreasing the emulsifier 
concentration or by increasing the oil concentration." 

Resistance of California red scale to HCN.—Laboratory experiments 
in the control of Chryscmphalus aurantii Mask. with HCN Ses control- 
led conditions are reported by C. I. Bliss a assistants, Whittier, 
+ e 
ind 
Calif. Mr. Bliss says that to determine e "effect of th e of foed 
upon the survival of red scale on lemon trees in the College grove at 
Whittier, a usa of twigs bearing leaves were exposed at 77° F. for 
25 minutes to varying concentrations of HCN. * * * On the three types 
of food, the sys on fruits were more resistant than those on twigs, 
those on twigs were more resistant than those on the upper surface of 
the leaves. So few scales collected on the lower surface of the leaves 
that no counts of this type were mede. The results from fruits were 
determined about 3 months prior to those on twigs and leaves, but a la~ 
ter analysis on fruits taken in a slightly different manner shows that 
the seasonal change did not modify the relative survival on the differ~ 
ent types of host material." 
(3) 
ck 
eet 
S 
Time-temperature effects on larvae of Ceratitis capitata Wied.--0. C. 
McSride and Tai Hee Hong, Honolulu, T. H., report that "In all tests 
to date we find the margin of safety in the heat treatment (that is, 
8 hours heating at 110° F.) is sufficient for all fruits studied. * * * 
ne series of tests on the Indian almord (kamani nut) containing 7,602 
© 
andl has just been completed. * * * At an average temperature of 
109.8 F. complete mortality of larvae and eggs in the kamani nuts 
is between 43 and 53 hours Our earlier experiments carried out in 
the Carrier machine nanwired abcut 25 per cent lenger to give complete 
mortality. The data show further that the percentage of larva emerging 
from the fruits decreases as the time of treatment increeses. Like- 

