~4e 
"cockroach plant" (Haplophyton cimicidum DC.), commonly known in Mexico 
as"lahierba de la cucaracha." This plant has been used since time im- 
memorial as an insecticide for killing cockroaches, flies, mosquitoes, 
fleas, body lice, and other insects. . In the year 1900 the plant was so 
abundant near Yantepec, Morelos,’ that it could be obtained for only the 
cost of cutting it. Decoctions prepared from this plant appear to act 
chiefly as a stomach poison,: and have been found very: toxic to two species 
of fruit flies (Anastrepha Judens and A. striata Shin.). The material 
produces ‘a paralysis, from which the flies rarely redover, although they 
may live:for several days. . The data obtained indicate that the material 
Will not ‘decompose and lose much of its toxicity when held for prolonged 
periods at a high temperature and a low humidity as 4 dried spray on 
glass plates. When held in solution at room temperature for approximate- 
ly a year and a half, however, its toxic properties were lost. The 
chemistry of this plant is only partially known, The Bureau of Chemistry 
and Soils has isolated and identified mannitol as one of its constituents. 
Thiodiphenylamine shows promise as a_ stomach poison.--E. H. Siegler 
and Francis Munger, of the Takoma Park, Md., laboratory, have found 
thiodiphenylamine (phenothiazine) very toxic to larvae of the codling 
moth (Carpocapsa pomonella L. ) in recent laboratory experiments. This 
material was brought to this Bureau's attention by the Bureau of Chemistry 
and Soils. The material is not readily wettable with water, but this 
difficulty has been overcome by mixing it with fuller'ts earth. Pre- 
liminary small-scale tests on foliage have not given any injury. The 
chemical is not available commercially, but it may be prepared by fusing 
sulphus (in the presence of a catalyst) with diphenylamine, a substance 
readily obtainable. 
Lime-sulphur with wettable sulphur effective against whitefly eges.-- 
W. W.. Yothers and R. L. Miller, of the subtropical fruit insect labora~ 
tory at Crlando, Fla., have found that lime-sulphur solution is effec- 
tive in controlling the citrus whitefly (Dialeurodes citri Ashm.) in the 
ege stage. It has been known for some time that the presence of sul- 
phur on citrus trees prevents the settling of larvae of’ this insect. 
Applications of lime-sulphur solution combined with wettable sulphur 
epplied during April, when the whitefly eges were in the later stages 
of embryonic development, gave nearly 100 percent kill of the eggs.- 
. This has the effect of extending the period during which whitefly sprays 
may be applied from a week or 10 days to 2 or’ even 4 weeks. 
JAPANESE AND ASIATIC BEETLES 
Depth of occurrence of Jap beetle population in soil.--The distri-~- 
bution of the general soil population of Popillia japonica Newn. with 
reference to depth of occurrence in the ground, as summarized from the 
empiric summary of the seasonal surveys conducted by H. Fox, Moorestown, 
N. J., for April is shown in the following table; 
