^74 INSECTICIDES, FUNGICIDES, AND WEED KILLERS. 



whilst adding .,\, of a lb. of 1)1 ue vitriol. The bouillie is made up to 10 

 gallons. 



Altises. — These multiple generations of small voracious insects, 

 numerous species of which exist, may be combated by copper arsenites 

 in powder or bouillie. 



Haltica aitvpelophaga, Guer. (altise of the vine, vine louse, Pucerotte). 

 — Galliot's bouillie, the composition of which is given under the head- 

 ing " Arsenite of Copper " (p. 276), and which is nothing but a bouillie 

 bordelaise containing a little Scheele's green, must be used in this 

 case, yet the same result is obtained by simply adding emerald green 

 to a cupric bouillie. 



PsylUodes affinis, Payk. (altise of the potato). — As an efficient 

 method of destroying fungi spores and insects, such as the dryophora 

 and the altise of the potato, Woods recommends bouillies consisting 

 of a mixture of 120 parts of emerald green in 1000 parts of bouillie 

 bordelaise, or 120 parts of emerald green and 750 parts of lime in 

 100 parts of water. 



Haltica Chalybea (plum altise). — Britton states that arsenical 

 bouillies destroy this altise. The perfect insects are destroyed by 

 0-2 per cent and the larvae by a 0-06 per cent bouillie. 



Cassida nebulosa. — In Saxony the arsenical bouillie has proved 

 itself more efficient than such insecticides as soapy emulsions of 

 petroleum, vinegar, slaked lime in powder. 



Silpha, L. — Opaque silph of the beet. 



Silpha atrata (black silph). — Silphs like the dryophora of the 

 potato are killed by cupro-arsenical bouillies with an emerald green 

 or Scheele's green basis. 



Treatment by Powders. — An intimate mixture of 1 kilogramme 

 (2-2 lb.) in 100 kilogrammes (220 lb.) of very finely divided gypsum, 

 -damaged flour, ashes, or a mixture of these different substances, is 

 •spread by hand on the dew-charged leaves. This dose suffices for 1 

 hectare {2^ acres). The operator must so manoeuvre as to have the 

 wind behind him. 



Treatment with Bouillies. — There is distributed, preferably by 

 the spraying machine "Eclair," a bouillie of 0-2-0-24 per cent of 

 Scheele's green, or 0*5 per cent of lime and 0"2 per cent of emerald 

 green. Four hectolitres of bouillie per hectare are applied, say 35 

 gallons per acre. Galliot's bouillie has been tried with success in the 

 North of France, and in Herault the larvye die in twenty-four hours. 

 Sorauer advises the use of a bouillie of 1 per cent Scheele's green and 

 '0-2 per cent of flour. Grosjeau, Debray, and Hollrung have aided in 

 popularizing this efficient method. 



Leptinotarsa decemlineata (Colorado beetle). — In America cupro- 

 arsenical bouillies have been used with success for many j^ears against 

 this voracious insect. This treatment has the advantage of destroying 

 many other insects at the same time and of protecting the plant against 

 potato disease, PliytophtJiora iiifestaus, De By. 



Gakruca calmariensis (galeruque of the elm). — In the U.S.A. 

 arsenical bouillies are used to destroy the larvae of this cJirysojnelide, 

 which rapidly causes the death of the finest avenue trees. But 



