-136- 
The strengths used were 0.1 gin. and 0.05 gm. per liter of water. Twenty 
larvae were used in each test. In the first all the larvae died after 
about 4 hours; and in the second, after about 5 hours. Dusting the in- 
fested plants with calcium arsenate, draining the water from the infested 
paddies, and applying a thin film of kerosene over the water to control 
the larvae gave encouraging results. Preliminary trials, under laboratory 
conditions, with derris powder also gave encouraging results, warranting 
further trials in the laboratory and in the field, 
Pachyzancla licarsi sa lis ("Walk. ) 
The Federated Malay States Department of Agriculture ( 125 ) in 1S37 
reported that the caterpillars inflicted severe damage to Bermuda, Blue 
Couch, and other grasses in experimental plots. A derris spray was effec- 
tive in controlling them. 
Phlyc taenia rubigalis (Guen.), greenhouse leaf tier, or celery leaf tier 
Howard ( 194 ) in 1933 reported tests to control this insect on celery 
in storage houses near Sandusky, Ohio. Dipping the celery in various con- 
centrations of pyrethrum and derris extract was not feasible, because cf 
demands that the celery be kept dry. It was decided that shaking was 
probably the most satisfactory control. 
Stahl ( 390 ) in 1934 reported derris dust not toxic to the leaf tier. 
A single test yielded the following results: 
Rotenone in dust 
Larvae killed in 6 days — 
Quarter- grown 
Half-grown 
lla 
ture 
Percent 
rcent 




1.8 

7.2 

Percent Perce nt 
0.1 8.7 
0.5 6.7 
1.0 16. G 
3.0 41.3 
No noticeable jffects resulted from the use of any of the dilutions against 
the larger larvae, and even the 3-percent dust gave unsatisfactory ' 1 s 
against the small larvae. 
The United States Department of Agriculture, Buroau of Enta 
in 1934 reported that additional tests have shown rather dofir.i 1 
rotenone compounds are not effective, and that pyrethrum is apparently a 
specific poison for the pest. 
In 1935 the United States Department of Agricul . bureau of Entomol- 
ogy and Plant Quarantine ( 441 ) reported that toxicity tests in the labora- 
tory showed that this insect is not affected by derris powd- . 
