- 103 - 
Dormestcs sp. 
Not nffrct-^d by derris.~V?»n dor Laan (252) in I936. 
Trogoderma vergi color (Crrutz) 
The adult i? definitely susceptible, "but thp larv=. is not su-^ceptible 
to dcrris. — Craufurd-Benson (90) in IQ'^S . 
Dynast idao 
Hct''roligu.s Claudius Klug. , a yam beetle • ' 
In 1929 the Imperial Institute of Great Britain( ?17 ) reported the 
results rf tests made liy the Entomological Branch of the Department of 
Agriculture in Figeria, Africa, with Tephrosia vogelii against yam bertles. 
Ysjns were soaked for a day or more in acueous extractions of the leaves of 
T. vogelii , and beetles were then put in a cage with the poisoned yam. The 
beetles readily fed on the yams, however strong the poison extract, without 
shovring any ill effect. Pieces of yajn were impregnated with the extract in 
vnc'Tum, and yam was .also coated vdth a mixture of casgava^tarch paste and 
Tcphrosia extract, but ?ill with negative results. The extract wp.s tested 
on small fish and found to be highly toxic. One of th:-' to^-ic principles 
of the plant v/as extracted with chloroform, and the extract vfas taken up 
in a very small Quantity of toluene and emulsified with water. This was 
then sprayed on yams, but the beetles vrould not touch it. ' 
Elateridae 
Limonius ( ct\'pus (Say) 
Morrill and I^acroix (289). ^^ ^9?^ tested cube-root powder against 
wirev'orms, the pri cipal species of vrhich is Limonius agonus (Say), now 
known as ectypus (Sa,y). It was applied to the vratrr used in connection 
with transplanting tobacco, but vas ineffective as a repellent, Dichloroethyl 
ether gevc the most rronising results. 
Ph^ Ictfs canus Lee. 
Campbell i^) in 1932 reported work done by Lehman, who tested a 
v/ireworm br'^it containing 10 gm. of ground whole vheat, 1 gm. of rotenone, 
and 6 gm of water at Valla. VTalla, Wash. The ball of bait was placed 
in a salve tin containing l6-mcsh soil, and 25 wirev;orms that had starved 
for 2 months were placed in the. tin. Five such tins were gi^t up and the 
larvae were examined after 2 vreeks. Sine the greatest mort^^lity wns only 
2'' pnrcent, the results were not considered nronising. 
Elaterir.ae (unidentified sp.) 
The gro^ind containing many larva*: vras soak.d with a suspension of 
derris powder containing 7 percent of rotenone and I7 percent of ether extract, 
the rotenone conc'htration in the suspension being 1:6,000, 200 liters ^eing 
used for a surface of 6 souare meters. The larvae appeared to be insensitive 
to derris -^ovrder anplicd in this manner. — Do Bussy ot al, (61) in I936, 
