- 503 - 
Other insects were subjected to the vapors from nicotine solu- 
tions and to the. exhalations from the dried films of nicotine on 
sprayed leaves. Under the most favorable conditions insects were 
thus killed, (pp. 95-98) . 
By means of histological methods nicotine was traced as -a stomach 
poison through the intestinal wall into the "blood, and nicotine as a 
fumigant was traced through the spiracles into. the tracheae and then 
to the central nervous system (pp. 106-113). 
nicotine spray solutions, without soap, do not pass into the 
tracheal, nor do they penetrate the integuments of insects. [in 
other papers] the author shows that soa.p solutions do enter the 
spiracles. . The fumes from nicotine used as a fumigant, the vapors 
from nicotine spray solutions, and the odoriferous particles (ex- 
halations) from evaporated nicotine spray solutions or from powdered 
tobacco pass into the tracheae and are widely distributed to all the 
tissues (p. 120). 
The author does not know just how nicotine paralyzes the nervous 
system, but it prevents the nerve cells from functioning. A review 
of the literature shows that its presence around the cells causes 
the same structural changes resulting in death as observed when other 
simple animals of the same kind are deprived of oxygen. In such cases 
it seems to kill physically rather than chemically, but the evidence 
presented does not conclusively prove this view. In the higher 
animals it may kill by interfering with oxidation in the cells (p. 120), 
FEYTAUD, J. (2138) 
1917. THE ACTION OF INSECTICIDES ON THE EGGS OP POLYCHROSIS BQTRANA 
SCHIFF. Bull. Soc. Etude Vulg. Zool. Agr. 16 (9-10, 11-12): 97-105, 
117-122. [in French. Abstract in Rev. Appl. Ent. (A) 6; 72-- 
73. 1918.] 
Nicotine destroys 80 percent of the eggs tree-ted, and nicotine 
bordeaux mixture prevents the hatching of 88 percent of the eggs. 
Nicotine slowly poisons the developing laxvae which die at the 
moment of hatching. 
_______ (2139) 
1917. F3CHEECHES SUE L'EUD_IviIS ET LA COCHYLIS DANS IE BORDELAIS EN 1914. 
Ann. Ser v. Epiphyties. 4 (1915): 218-265, illus. [Abstract in 
Rev. Appl. Ent. (A) 7: 457. 1919.] 
Pyrethrum which only prevents development of l/6 of the eggs 
of Polychrosis botrana had the same action as nicotine, the larva 
becoming poisoned at the moment by eating its way out of the egg. 
McINDOO, N. E. , and SIEVERS, A. F. (2140) 
1917. QUASSIA EXTRACT AS A CONTACT INSECTICIDE. Jour. Agr. Res. 10: 
497-531, illus. 
