220 



EEPORT UPON COTTON INSECTS. 



In the present state of our knowledge it seems that the most effectual 

 means of destroying the cotton-caterpillar is by the use of poisons, 

 either in the moist or dry condition. In the former case, the poisonous 

 substance is dissolved or suspended in water ; in the latter, it is mixed 

 with flour, gypsum, or other innocuous powder, which serves to dilute 

 it, and in some cases to aid it in adhering to the plant. The ground 

 covered by my experiments with poisons may be seen from the follow- 

 ing tables : 



I. TO TEST THE EFFICACY OF THE SUBSTANCES. 



^ (a) London purple, suspended in water. 



(b) Gray arsenic, suspended in water. 



(c) Paris green, suspended in water. 



(d) Texas worm-destroyer, dissolved in water. 



(e) Gray arsenic, in Fowler's solution. 

 (/) Oil of turpentine, in water. 



(</) Kerosene, in water. 

 (h) Carbolic acid, in water. 

 ^ (a) London purple, in Eoyall's mixture.* 



jj Dry. { W Gray arsenic, in Eoyall's mixture. 



/ (c) Paris green, in Eoyall's mixture. 



A Wet. 



II. TO TEST THE ADHESION OF THE SUBSTANCES. 



A. Wet. 



B. Dry. 



() Poisons suspended in water without flour-paste. 



(b) Poisons suspended in water with flour-paste. 

 (.) Poisons mixed with flour. 



(&) Poisons mixed with flour and gypsum. 



(c) Poisons mixed with flour and rosin. 



(d) Poisons mixed with flour and dextrine. 



(e) Poisons mixed with flour, rosin, and dextrine.t 

 (/) Poisons mixed with flour, gypsum, and rosin. 

 (g) Poisons mixed with flour, gypsum, and dextrine. 



(h) Poisons mixed with flour, gypsum, rosin, and dextrine. 

 (i) Poisons mixed with gypsum, rosin, and dextrine. 

 (/.) Poisons mixed with gypsum and rosin. 

 (I) Poisons mixed with gypsum and dextrine. 

 i. (m) Poisons mixed with gypsum. 

 All of my wet poisons were applied by use of Whitman's fouutain- 

 punip, No. 2. Where small quantities were used, one man carried a 2- 

 gallori water-bucket, and another preceded him, working the pump. 



* Royall's patent : Flour, one barrel, 196 pounds; Paris green, 9 pounds; dextrine, 

 10 pounds ; rosin, 12 pounds. 



The ingredients being in a fine powder, are sifted to remove lumps, after which they 

 are thoroughly mixed. Other poisons may be substituted for Paris green. 



11 bid. 



