58 



plant, they decrease the weight of the grain, but do not actually 

 destroy it. Contarinia tritici, on the other hand attacks the grain 

 directly and destroys it, and although this may lead to a sHght 

 increase in the weight of the uninfested grain, it can in no case 

 compensate for the actual damage done. 



GOMILEVSKY (V.). flflOBMTblfl paCTeHJfl, M3Ti KOTOpbIXT* MOWHO 



MSBneKaTb cocraBbi aha 6opb6bi ctj BpeflMiejiflMM caAa. [Poisonous 

 plants, from which insecticides for orchard-pests may be pre- 

 pared.] — « CaflOBan BM6niOTeKa.» [Orchard Lihranj Series]. — 

 Supplement to « flporpeccMBHoe CaflOBOACTBO n OropoAHn- 

 HeCTBO.» [Progressive Fruit-growing & Market-gardening], Petro- 

 grad, 1915, 32 pp. 



The principal poisonous plants of the Eussian flora are described 



with special reference to their medical and economic importance, and 



particularly as regards their possible use as insecticides and fungicides. 



The poisonous quality of the fungus, Claviceps purpurea, depends, 



according to some authors, not so much upon the ergotin and ecboline 



contained in it, but on the presence of ethereal oils. An extract of 



this plant, in the proportion of about 1 part to 10 parts by weight of 



water, kills Aphids, Psylla, thrips and probably also other sucking 



insects and those unprotected by hairs. The poisonous qualities of 



Amanita tnuscaria probably depend on the presence of volatile matter 



and the alkaloid amanitine (muscarine). An extract of the whole 



fungus is likely to prove effective against all kinds of gnawing insects 



and their larvae. The spores of Lycoperdon bovista may be used in 



the same way as flowers of sulphur ; insects covered with this powder 



■either perish from its mechanical effects or are poisoned by it. As 



the foliage of Taxus baccata (yew) is not eaten by insects, it is suggested 



that dusting with a powder of the dried leaves or spraying with an 



extract of them may prove efiective against insect pests. An extract 



of Colchicum autumnale (meadow saffron) contains the poisonous 



alkaloid colchicine, the solution of which is facilitated by the addition 



of alcohol ; molasses may be added to the liquid to make it adhesive. 



A fine powder prepared from the stalks of Veratnmi album, L. (white 



hellebore) is now used as a fungicide and insecticide in America ; an 



extract of this powder (about 1 oz. in 3 gallons of water) is considered 



preferable, as the powder is highly poisonous. Daphne mezereum, L. 



(spurge-flax) is well known in medicine ; the author has never observed 



any insects on this plant, but frequently found underneath it dead 



beetles, flies and wasps ; he suggests experimenting with an extract 



of the berries or bark or even of the whole plant on various forest pests, 



such as Lytnantria dispar, L. (Psilura) monacha, Malacosoma neustria, 



etc. Aconitum napellus (monk's-hood) is also suggested as a possible 



insecticide ; some years ago the author witnessed the deadly effect 



of a few drops of an extract of this plant on stag beetles, Imcanus 



cervus, the solution being dropped on the junction of the thorax and 



abdomen. To prepare the extract, one part by weight of the chopped 



plant is placed in six parts of water at a temperature of 85°-105° ¥., 



and left for 24 hours at the temperature of the room ; the liquid is 



then strained through cloth and the residue pressed out. It is then 



again mixed with three parts of water and after 24 hours the process 



