-30- 
affect mortality, but dew and light rain before or after the dusting 
increased the mortality. 
alacosoma pluvialis (Dyar), the western tent caterpillar 
Campbell ( 60 ) in 1932 reviewed unpublished work by Robinson of 
Oregon, who reported a few tests with rot -none in an insectary. Most 
of the caterpillars that ate any of the foliage treated with rotenone 
at 1:1,890 and 1:1,260 died. Robinson noted that the toxic action 
was slow and that many of the caterpillars placed on the sprayed appa 
foliage fell to the table below. Ee therefore concluded that rotenoni 
is repellent to the larvae. However, Campbell surmised that the catg 
pillars that fell from the foliage might have been irritated by h-nd- 
ling. 
Lasiocampidae (unidentified sp.) 
Kopp ( 24.2 ) in 1924-, in a review of the use of derris as an insec 
cide, stated th^t derris powder has given excellent results against 
gtelacosoroa (500 gm. to 32-800 liters of water). 
Mclndoo and Sievers (263.) in 1924- reported that a hot^water ex' - 
tract of the stems of a fish poison, Cracca villosa purpurea (T ephrosl 
purpurea ) , had no effect on tent caterpillars, and that derris powder 
used as a "umr'g^nt was ineffective against small tent caterpillars* 
The Institute of Physical and Chemical Research (214.), Tokyo, 
Japan, in 1927 reported that Neoton at 150, 225, and 300 gm, plus 
4.50 gm. of soap per 4-0 imperial gallons of water gave mortalities of 
56, 60, and 72 percent, respectively, after 24. hours; and of 82, 78, 
and 96 percent, respectively, after 30 hours. Neoton at 225 gm. plus 
675 gm. of soap per 4.0 imperial gallons of water gave 100-percent 
mortality of the Japanese tent caterpillar. 
According to the Harder Extermination Service, Inc., in an adver- 
tising leaflet in 1934, its harder Rotenone Plant Spray is used at l:4-( 
for killing tent caterpillars. 
Tischler ( 4-13 ) in 1935 studied the mechanism of how derris kills 
insects. Tests made with insects such as tent caterpillars lead to 
the conclusion that derris inhibits the utilization of oxygen by the 
tissues and that its detrimental effects are general rath, r than spe- 
ific to any organ. 
Haude in 1939, in advertising literature published by John Powel 
& Co., New York, N. Y., recommended a cube or derris spray (/+ lb. of 
powder c.-.ntaining 4 percent rotenone per 100 gal. plus 4- lb, rosin-resi- 
due emulsion) against the test caterpillar on wild cherry, apple, 
and hawthorn. 
Limacodidae 
i- a rasa consocia 'Valk, 
Yago ( 502 ) in 1933 wrote that this species, formerly abundant in 
