- 145 - 
200. and DAVIDSON, R. H _ , . ---,,-;■ 
1935. Derris sprats or dust's' ,give /best control x>f' cabbage 
worms, in' Ohio. ;U. S. Dep ( t. Agr. ,"Bur. 'Ent. and 
Plant. Quarantine' News', Letter. 2 (11): 22, mimeo. 
201. and i.IASON, H. C. 
1937. Results of experimental, work: with- rotenone-bearing 
materials for the 'control of vegetable insects. 
Ohio Vegetable Growers' Assoc, Proc. 22: 12-23. 
202. HOWARD, N. F. , and MASON,. H. C. - 
1936. Experiments, against the Mexican bean beetle. In Ohio. U. S. 
Dept, Agr., Bur. Ent. and PI, Quarantine News Letter 
5 (4): 15-16, mimeo.. 
203. MASON, H. C. , and DAVIDSON, R. H. . : . . : '. . '. - 
1935. Derris for the control of certain vegetable . insects. 
Ohio Vegetable Growers' Assoc. Proc. 20: 21-25. 
204. HOFE, E. I. . ."^i 
1936. Cube dust mixtures effective against -tobacco flea beetle. 
U. S. Dept, Agr., Bur. Ent. .and Plant Quarantine News 
Letter 3 (8): 15, mimeo. 
205. HOYER, D. G. , and LEONARD, M. D. 
1936. Toxicity of rotenone po\?ders. Soap 12 (3): 109. 
206. HUCKETT, H. C. 
1937. Common insect pests of New York No. 9. The, asparagus 
beetle. N. Y. State Agr. Expt. Sta. (Geneva) Circ. 
No. 171, colored illus. 
207. . i 
1938. Recent problems on Long Island -in the control of bean 
insects. Jour. Icon. Ent. 31 (2); 266-270. 
208. ' EOT, E. B. 
1937. Horticultural oil spray. U. S. Patent 2,087,599; 
issued July 20, 1937; applied for September 8,. 1932; 
assigned to Stanco, Inc. 
209. HUTSON, R. 
1936. Derris and pyre thrum for insect control. Mich. State 
Col. Agr. Appl. Sci. Ext. Bull. 164, 4 pp., illus. 
210. IDAHO AGRICULTURAL EXPERIMENT STATION , . 
1936. [Cube- kaolin "*uii 1 ,.] Science aids Idaho farmers. Idaho 
Agr, Expt. Sta. Ann. Rept. 1935. Bull. No. 220: 31. 
211. 
1937. [Derris.] Idaho Agr. Expt. Sta. Ann. Rept. 1936. Bull. 
No. 221: 32. 
