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RUGGLES, A. G. (2251) 
1931. PRELIMINARY NOTES OH THE BIOLOGY AND CONTROL OF THE PI1IE LEAF 
SCALE, CHION ASPI S PINIFOLIAS FITCH. Jour. Scon. Snt . 24: 115-119. 
[Abstract in Rev. Appl. Ent. (A) 19: 345-340. 1931.] 
Experimental work in 1927 and 1928 showed that this scale coulci 
"be controlled by careful applications of Volck oil and nicotine, "but 
a further study was "begun in 1930 to devise better spraying compounds. 
Tests showed that it can "be controlled in the middle of the hatching 
season "by using 1 percent Volck light oil with nicotine s\ilphate and 
nicotine sulphate and soap. 
TTILC.0X0N, F., and HARTZELL, A. ' (2252) 
1931. SOME FACTORS AFFECTING THE EFFIENCY OF CONTACT INSECTICIDES. I 
SURFACE FORCES AS RELATED TO T7ETTING AND TRACHEAL PENETRATION. Cont: 
Boyce Thompson Inst. 3 (3): reprint, 13pp., illus. [Abstract in Rev 
Appl. Ent. (A) 19: 267-268. 1931.] 
The toxicity to Aphi s rumicis L. of nicotine solutions alone or 
containing calcium caseinate, penetrol, or sodium oleate was determined 
and compared with measurements of surface tension and angle of contact 
It was found that the toxicity followed the same order as the spreading 
coefficient. 
BRITTON, 17. E. (2253) 
1932. CONNECTICUT STATE ENTOMOLOGIST, THIRTY-FIRST REPORT 1931. Conn 
Agr. Expt. Sta. Bull. 338, pp. 499-603, illus. [Abstract 'in Rev. 
Appl. Ent. (A) 20: 701-703. 1932.] 
A spray consisting of 1 1/4 gal. lime-sulphur, 1 pt. nicotine 
sulphate, and 100 gal. water, with 1 lb. iron sulphate added, gave 
the best results against the adilts of leafhoppers ( Typhlocyba pom a ria 
McAtee) on apples. Tests against aphids showed that variations in 
temperature and humidity do not affect to any appreciable extent the 
toxicity of nicotine sulphate when used with an activator, such as 
penetrol. There is little doubt that the activator increased the 
toxicity of the spray, although the toxicity of nicotine sulphate at 1 t> 
2,000 and penetrol at 1 to 200 did not equal that of nicotine sulphate a' 
1 to 800 alone (p. 702). Aphids ( l.iyzu s circumflexus Buckt . ) were found 
infesting Gladiolus, oorms in storage. The infestation was controlled by 
soaking the corms in nicotine sulphate (1:400) for 30 minutes. 
DRAKE, C. J., ET AL. (2254) 
1932. PRELIMINARY EXPERIMENTS TJITK APHIDS AS VECTORS ^F YELLO',7 D7ARF. 
Iowa State Coll. Jour. Sci . 6 (3): 347-355, illus. [Abstract in Rev. 
Appl. Ent. (A) 20: 706-707. 1932.] 
