- 123 - 
particularly for use on vegetables and for late-season sprays on 
fruits, in order to avoid dangerous spray residues. Since these 
preparations are new, their limitations are not known and practical 
tests must "be made to determine the truth of the representations under 
which they are sold and to make sure that they will not cause injury 
to plants. 
Georgi, Lambourne and Teik (162) of the Federated Malay States 
Department of Agriculture wrote in 1936 that because of growing compe- 
tition from cube root ( Loncho carpus sp.) the necessity for standardizing 
high-grade Derris becomes of greater importance. 
Tattersfield (400) in 1937 published a report of the work of the 
Department of Insecticides and Fungicides of the Rothamsted Experimental 
Station, England, for 1918-1936, in which the investigations on Derris, 
Lonchocarpus, Tephrosia, and other fish poisoning plants are reviewed. 
McDonnell (275) in November 1937 spoke as follows in his address 
as president of the Association of Official Agricultural Chemists; 
"The most recent development in the field of new products is the 
use of rotenone-bearing plant material and extractives, which are highly 
toxic to many forms of insect life attacking plants and animals and 
those occurring in the home. Rotenone is a constituent of many plants 
of the Leguminosae family and at present the principal commercial sources 
are Derris elliptica (usually referred to merely" as "derris") and 
Lonchocarpus n i c ou (known commercially as "cube"), which are imported 
from the British and Dutch East Indies and the northern parts of South 
America. It has been known for many years that the roots of these 
plants contain ingredients highly toxic to insects and some other forms 
of animal life, but it is only during the past five years that their 
commercial use for insect control has reached large proportions. There 
are now scores of commercial insecticides on the market that owe their 
activity to these materials or extracts made from them. In 1936 this 
country imported more than two and one-half million pounds of derris 
and cube in the form of unground and powdered roots. The importations 
for 1937 will greatly exceed this figure." 
F. L. Campbell (6l) in 1937 presented information on derris, 
cube, devil's shoestring, and pyrethrum before the Ohio Vegetable 
Growers Association. The actions of rotenone and the pyrethrins on 
insects are compared. 
Boam, Cahn and Stuart (30) in 1937 reported on the identification 
of tephrosin and deguelin from different sources. Clark is .credited 
with having isolated pure tephrosin, m. p. 197-198, from Lonchocarpus 
nicou roots in 1930 and Boam, Cahn and Stuart in 1936. 
