REPORT OF THE ENTOMOLOGIST. 



313 



September 5 some cotton badly infested witli newly-hatched caterpillars was }ioi 

 snned, as follows : 



Date. 



Sept. 5,1870.. 



Name of poison. 



Paris green 



<lo .... 



do .... 



Kerosene .. 

 Turpentine 



C 



24 ounces 

 16 ounces 

 24 ounces 

 10 fl. OZ.S. 

 20 a. 0Z8 . 



c? 



3 gallons . 



^•■S 



S3 

 c2 



Manv. 



Do. 



Do. 

 Few. 



Do. 



lu all we poisoned a little less that three acres this time, using only about half a 

 barrel on section 22. One hand worked the pump, wetting six rows at a time ; another 

 followed him with the bucket of poison. Previously I had caused a barrel in the 

 middle of the field to be filled with water. In this I suspended the poison, having the 

 men replenish it as often as necessary. About four gallons each of the kerosene and 

 turpentine mixtures were u.sed. 



The next day, when I examined the Paris-green sections, I fofand many worms dead 

 on each of them. When I rubbed the leaves with my hand, or sprinkled water over 

 them, I could not see but that one adhered as well as another. Here and there a leaf 

 was badly scorched, and some few forms were injured; but, taken as a whole, the field 

 suffered little. Here I noticed what was also seen before and afterward, namely, that 

 a leaf may be completely covered with Paris-green sediment and yet show no scorch- 

 ing; but where the dead spots appear on the leaves there may be little of the poison. 

 Paris-green being practically Lnsoluble in water, I am unable to account for this. 



On the 8th of September I noted that the cotton on which Paris green was used 

 three days before was uninjured by the woitqs, though a few were still eating, most 

 of these having hatched after the poison was applied. But where I used kerosene or 

 oil of turpentine the cotton was almost leafless, these substances having injured some 

 of the leaves and killed a considerable number of larvae, but not enough to save the 

 crop. 



September 10, a number of gallons of water, containing from a half teaspoonful to 

 a teaspooirful of carbolic acid per gallon, were applied with the fountain jiump. This 

 water was stirred so that the acid was suspended through it as very small globules. 

 It was found to kill some caterpillars, but by no means enough to save the cotton ; 

 and, used in these proportions, it injured the cotton considerably. More water, con- 

 taining kerosene and oil of turpentine in varying quantities, was applied ; but, like 

 the last, I found that it did not effectually destroy the worms, even when strong 

 enough to seriously injure the cotton. 



B. — DRV POISON. 



In the afternoon of August 22 I poisoned four sections with dry poison.?, as shown 

 in the annexed table. "Where flonr was used with either rosin or dextrine, or both, 

 the proportion was that used in Royall's patent. Where gypsum was used, it replaced 

 the flour, bulk for bulk, in this series. 



Date. 



An?. 22,1879 



I 2 



Name of poison. 



v. 

 S 



o " 



f Flour. ...^ 1 



London purple ■' Dextrine. > ■ 



( Itosin ) I 



It>-- $|;^«y.----VU hours.. <! 



I Pans green < Dextrine. > ^ 



, ( Kosin ) 



I London purple ; Flour 



i Paris jtreen \ Gypanm J 



Fair , 



Good 



Fair . 

 Good 



3.9 



Fair quantity. 



Do. 



Do. 



Very little. 



