-98- 
■4 
The Imperial Institute ( 211 ) in 1938 reported information on derris 
taken from a half-yearly report of the Federated Malay States Department 
of Agriculture. Repetitions of earlier experiments on the asphyxiant 
properties of derris had he en carried out. Fresh crushed roots of derris 
from 3 localities all exerted a lethal distance effect on larvae of this 
species. The rotenone content, dry oasis, of the roots used ranged from 
7.04 to 0.34 percent, but this did not appear to affect its killing power. 
Fresh-water extract of derris roots gave negative results, as did pure 
rotenone 13,25 percent, ether extract 30.2 percent (dry basis) also gave 
negative results j but when this powder was ground to a paste with water it 
exerted an action similar to fresh crushed roots, but slightly less rap- 
idly. Controls to all these experiments gave negative results. Spraying 
experiments with derris extracts were temporarily discontinued owing to 
inaccuracies of the apparatus. Dusting was tried with more success and 
1,000 larvae were dusted, with fairly consistent results. The best dilu- 
tion of dust appeared to be 10 percent of powdered derris and 90 percent 
of talc. Results have been expressed as Weight of dust projected and re- 
duced to weight of derris powder in the mixture and plotted against per- 
centage kill, thus giving a more accurate picture. 
Taeniocampa gothica (L.) 
Gimingham and Tattersfield ( 161 ) in 1928 reported the results of lab- 
oratory tests With nonarsenical insecticides for control of biting insects. 
An extract of black haiari stems was tested on ( Monima ) . Taeniocampa 
gothica . The insects were slightly affected; there avas appreciable feed- 
ing but very little growth. Soap, 0,25 percent, was added to this extract. 
Tattersfield and Gimingham ( 401 ) reported that young larvae of this noctuid 
moth were highly resistant to an old extract of black haiari stems. 
Triphaena pronuba (L., ) 
The Experimental and Research Station of the Nursery and Market Gar- 
den Industries' Development Society Ltd., of Cheshunt, England ( 115 ) , in 
1939 reported .that derris dust was effective against caterpillars of the 
yellow underwing moth on carnations. 
Phalaenidae (unidentified sp.) 
Derris was not effective in a bait fed to cutworms, either in the in- 
sectary or in the field; but derris'' spray was observed to kill certain 
noctuid moths. — Kolsall et al. ( 233 ) in 1926. 
The Institute of Physical and Chemical Research ( 214 ) Tokyo, Japan, 
in 1927 reported that 1 pound of Nooto'n in 24 imperial gallons of water 
had no effect on cutworms. 
Campbell (60) in 1932 reported experiments by Reynolds, who fed cab- 
bage-leaf sandwichos containing an unknown quantity of rotenone to undeter- 
mined species of cutworms. Although tho loaf disks were treated with ro- 
tenone suspension up to 1:200, the larvao fed freely and were not affected 
by rotenone. This unidentified cutworm is the only lopidoptorous larva so 
far tested that seems resistant to rotenone as a stomach poison. 
