..-114- 
281. BUREAU : OF . ANB5AL- INDUSTRY 
1940. (perr-isv] U. S. : Dept. Agr. , Bur. Animal Indus. Ann. Rpt. 
.1940: 81-82. 
282. BUREAU' OF ENTOMOLOGY 
1923. [Derris.] U.S. Dent. Agr., Bur. Ent. , Ann. Rpt. 1923: 29. 
* - • # 
, 2.83. .— BUREAU OF ENTOMOLOGY 
1$27. [Derris.] U. S. Dept. Agr., Bur. Ent. Ann. Rpt. 1927: 23. 
284. BUREAU OF ENTOMOLOGY 
1929. [Derris.] U. S. Dept. Agr., Bur. Ent. Ann. Rpt. 1929, 39 pp. 
285. BUREAU OF ENTOMOLOGY 
1930. [Derris.] U. S. D e pt. A^r. , Bur. Ent. Ann. Rr)t. 1930, 76 pp. 
286. — BUREAU OF ENTOMOLOGY 
1931. '[Derris.] U. S. Dept. Asr., B ur. Ent.' A nn . Rpt. 1931, 87 pp. 
287. -BUREAU OF ENTOMOLOGY 
1932.' [Derris.] U. S. Dept. Agr., Bur. E nt. Ann. 'Rpt. 1932, 38 pp. 
288. BUREAU OF ENTOMOLOGY 
1933. [Derris.] U. S. Dept. Agr., £ ur. Ent. Ann. Rpt. 1933; 47 pp. 
289. .BUREAU OF . ENTOMOLOGY 
1934. Rotenone-bearing plants. U. S. Dept. Agr., Bur. Int. Ann. 
Rpt. 1934: 9. 
290. BUREAU OF ENTOMOLOGY AND PLANT QUARANTINE 
■ 1936. [Derris and. cube,] . U. S. Dept. A^r. , Bur. Ent. and Plant 
Quar. Ann. Rpt. 1936: 58, 59, 61, 67, 76, 86, 87. 
291. BUREAU OF ENTOMOLOGY AND PLANT QUARANTINE 
1938. [Derris.] U. S. Dept. A^r. , Bur. Ent. and Pl«nt Qpstr. Ann. 
Rpt. 1938* 84 pp.. . : 
