- 488 - 
The hispid (B rontisp a f roggatti Sharp) may be controlled 
"by shaking a suspension of lead arsenate or nicotine and soap 
solution into the heart of the leaves of affected trees from a 
bottle with a perforated cork. 
BARBIERI, N. A. (2088) 
1933. TABACIN OH THE TOXIC PRINCIPLE OP TOBACCO. TF.E INSECTICIDAL 
ACTION OP TABACOL. Rend. Accad. Naz . Lincei, CI. Sci. Pis. e 
Mat. Nat. (6) VII, pp. 764-768; XVII, No. 5,. pp. 402-409, illus. 
[Rome] 1928 and 1933. [in Italian. Abstract in Rev. Appl. 'Ent. 
(A) 21: 630. 1933.] 
The first of these papers describes methods of analyzing 
tobacco. One of the fractions obtained contains t abac in , a 
glucoside with a distinct acid reaction, highly soluble in 
water or alcohol, but insoluble in ether. A 2 percent cold potash 
lye divides it into its components, tabacol, tabacinic acid, 
and sugar. At 110° C. tabacin produces irritant vapors of tabacol. 
When treated with a hot concentrated potash lye, tabacin loses a 
large amount of ammonia and changes into nicotine. 
In the second paper the author considers tabacol to be an 
ideal insecticide, as it acts on the nervous system of insects, 
causing instant paralysis, and does not injure plants, even at 
100 percent strength. It has an alkaline reaction and is highly 
soluble in water. Between 40° and 60° C it emits irritant, poisonous 
vapors. Insects (including L asioderma serricorne F.), spiders and 
worms placed in a litre flask in which 1 cc. of tabacol had been 
vaporized were killed at once. A solution of 1 per mille may be 
used as a preventive spray, while one of 1 percent destroyed aphids. 
UTithin 1_ minute , a 2 percent solution killed Lepidosaphes pinnaef ormis 
, Bch. , Keliothrips haemorrhoidalis Bch. , Tetranychus telarius L. , 
Aspidiotus hederae Vail. , and ants. Dipterous leaf -miners were 
killed by fumigation or by immersing the leaves for an hour in a 
2 percent solution. In hot-houses, a 2 percent solution should be 
used as the tabacol left on the leaves after the water has evaporated 
prevents reinf estation for some time. A 1 percent solution injected 
into the soil killed worms without injury to the roots of plants. 
In experimental work in 1932 in France and Belgium and in 1933 in 
Italy, a 2 percent solution destroyed pests on a large number of 
. plants without any injury to the foliage. Beet flies (Pegonia 
hyoscyami ) as well as Cecidomyia corallina and their larvae are 
destroyed by exposure to the fumes for 1 hour. 
5. Greenhouse Pests, 1885-1929 
BOUCHE, J. (2089) 
1885. INSEKTEN-VERTILGUNG DURCH VERDAviPFEN VON TABAKSAFT ODER VERBRENNE 
VON TABAKPAPIER. Jahrb. Gardenkunde u. Bot. 2: 447-448. 
Aphids on greenhouse plants were fumigated by placing a 
particular tobacco juice over a low fire. This juice was a waste 
