312 INSECTICIDES, FUNGICIDES, AND WEED KILLEES. 



Nothing in the way of forcing or artificial heat is required. Lilacs 

 bloom within two weeks of being chloroformed, and lilies of the 

 valley are hardly so long in coming to maturity. — Added by Trans- 

 lator.] 



Action of Chloroform Vapour on Spores. — Wheeler corapaied 

 the action of formol, chloroform, ammonia, and carbon disulphide on 

 the spores of TUletia with the view of discovering a practical pro- 

 cess for the disinfection of seed-corn by anticryptogamic vapours. He 

 found that only the vapours of formol entirely, accomplished the end in 

 view. Seed-corn is placed in a tube and the vapours of anticryptogamic 

 substances are passed through it by aid of an air current. Wheeler 

 in that way obtained the following results : — 



TABLE LXI. — Showing the Disinfectant Capacity of AnticrijiAogamic Vaijours 

 on Seed-Corn. 



Action on Insects. — Chloroform is poisonous to insects, its vapour 

 kills them. 



Use. — Coupin advises that in the struggle against the insects in- 

 festing granaries, carbon disulphide be replaced by chloroform which 

 has the advantage when used on dry gi-ain of not damaging it like 

 carbon disulphide. 



Coccides. — Reh found chloroform vapour acts very energetically 

 against coccides. Coquillet who tried it against cochineal of the orange- 

 tree and lemon-tree did not record perfect results. 



114a. Carbonic Oxide, CO.— Preparation. — This gas is formed 

 oneverv occasion that there is incomplete combustion of carbon owing 

 to an insulliciency of air to form carbonic acid [to which it l)urns in air]. 



Properties. — Carbonic oxide is a poisonous gas. In doses of 4-5 

 per cent in the air it causes the immediate death of animals. This 

 action is explained by the way it behaves to the htemoglobin of the 

 blood. By the combination which it forms with the latter it annuls 

 more or less completely the property of the globules to fix oxygen. 



Use. — Carbonic oxide is used to kill the chrysalis of the silk-worm 

 by submitting the cocoons for eight hours to the action of this gas. 

 Coquillet also tried unsuccessfully to destroy cochineals by the use of 

 this gas. 



Alcohols. — The alcohols enter into the composition of many 

 insecticides because they are capable of mixing in all proportions with 



