46 . 
reached and maintained for an honr. Filtered while hot into another Mason jar, 
sealed and set aside to cool. After cooling the filtrate was emulsified as before. 
This emulsion was used in experiments 16, 17, and 18. 
Experiment 16. 
October 24 (11:45). — Four and one-half per cent solution. Larva?, 9 in number. At 
5:10 7 larvae, half grown or over, though quite active, appear slighly affected; 2 are 
badly affected. 
October 26. — Three large ones alive and feeding; another is alive, but not active; 
1 has webbed up, and 4 half-grown ones are dead. 
October 29. — One live pupa; 2 webbed; 2 dead, including the one which had webbed 
October 26. 
October St.- -Two more pup®, 1 well formed, the other not. 
November 29.— Two iniagos issued; the imperfect pupa dead. 
Experiment 17. 
October 24 (11:35). — Thirteen percent solution. At 4:48, 3 nearly grown hardly 
able to crawl. All are evidently uncomfortable. 
October S6. — All but one are dead. This one is making a poor attempt at pupating. 
None fed any before dying. 
October 29. — Succeeded in pupating, and is still alive. Later, pupa dead. 
Experiment IS. 
October 30 (4:15). — Twenty-one per cent solution. Number of larvae, 10; almost 
grown. At 4:30 all are off the fresh, unsprayed branches and tumbling about in the 
cage. All but one are in convulsions; the one exception is not active — in fact, can 
not crawl. 
October 31 (9:30 a. m). — Evory effort to place the larvae upon the branches proves 
useless today,, as it did last evening. The larvae have not the slightest control of 
themselves. 
November 2. — All are dead. In experiment 16 the foliage was unharmed; in 17 
slightly scalded, and in 18 badly scorched. 
SIMPLE COLD-WATER DECOCTION. 
Three ounces pyrethrum were added to \\ pints rain water and left to soak over 
night at 68° F. Filtered the next morning and the filtrate kept in sealed Mason jar. 
Decoction prepared October 7 to 8. Used in experiments 19, 20, and 21. 
Experiment 19. 
October S (4:55 p. m). — Full strength decoction sprayed upon larvae of all sizes en a 
branch of cotton in the field. The smaller ones began dropping off almost immedi- 
ately. The larger ones showed no desire other than to get away from their moist- 
ened quarters. 
October 9. — Many Avorms feeding, some nearly grown, others very young, and but 
recently hatched, none appearing much affected; 16 larvae, all less than half grown, 
dead. 
October 10. — Can now tell which ones will survive. Three almost grown, 5 halt 
grown, and 7 very young. The dead numbered 22, all very young and recently 
hatched. 
In experiment 20 only half strength of the decoction was used. This gave even 
less effective results than the full strength, and need not be presented. 
The filtrate of the fresh decoction on October 8 Avas clear, and had rather a pleas- 
ant smell. Subsequently, though kept in a sealed Mason jar, it became decidedly 
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