f 
of sulphur dust. We can state that this treatment (except for such. 
very prostrate plants as violets) is not at ali effective in the Southeast. | 
Sulphur mixed with water was sprayed on infested cotton. Exam-_ 
ination showed that the red spiders were in no way affected. When. 
soft soap was added to this same spray, however, the resulting mor- 
tality was from 50 to 99 per cent, depending on the thoroughness 
with which the preparation was kept mixed. 
Potassium sulphid has been tested at strengths of from 4 ounces to 
3 gallons of water to 1 ounce to 4 gallons of water on cotton, sweet — 
peas, hollyhock, beans, and violet. The former concentration slightly 
damaged the foliage and a mixture of 1 ounce to 2 gallons of water 
was found to be ideal. This spray commends itself from every view- 
point—cheapness, simplicity of preparation, ability to kill quickly, — 
and safety to fohage. 
Both homemade and commercial lime-sulphur sprays were carefully 
tested on cotton, beans, and sweet peas. The mortality on cotton 
and beans was practically complete, but the results on infested sweet 
peas were invariably unsatisfactory. With the addition of neither 
flour paste nor gelatin was this substance effective on sweet-pea foliage. 
This is quite in agreement with Parker’s results, and is explainable 
through the fact that the pubescent surface of the sweet-pea leaf pre- 
vents the even spreading of the insecticide. On cotton, beans, and 
several other hosts hme-sulphur is a perfect red-spider spray. 
Sodium sulphid was tried repeatedly on infested cotton and beans. — 
The greatest mortality obtained against red spiders on beans, a host 
well adapted to red-spider spraying, was 58 per cent, and the prepa- 
ration was so strong as to damage the leaves somewhat. The addi- 
tion of fish glue resulted in a mortality of 95 per cent, but in this 
case it is believed that much of the destruction was caused by the 
mechanical action of the glue. 
64 BULLETIN 416, U. S. DEPARTMENT OF AGRICULTURE. 
NICOTINE PREPARATIONS. 
Nicotine sulphate and fish-oil soap or miscible oil.—Nicotine sulphate 
used by itself is very unsatisfactory as a red-spiderspray. This prep- 
aration was tested at strengths of from 1: 400 to 1: 800 against red 
spiders on cotton, beans, sweet peas, and violets. The best results 
were secured on infested cotton, using the extract 1: 640, a mortality 
of 70 per cent being obtained. When combined with fish-oil soap 
(one-half ounce nicotine sulphate, one-fourth pound fish-oil soap, 2 
gallons water) its effectiveness was pertect. 
The mixture of nicotine sulphate (1 to 500) and a miscible oil 
(1 to 40) also gave complete mortality. The addition of flour paste 
had almost no noticeable effect in increasing the percentage of mor- 
tality. We believe, in the case of the excellent results obtained from 
the use of combined nicotine sulphate and fish-oil soap, and of com- 
