202 FUMIGATION METHODS 
the bugs were destroyed. The season had so far ad- 
vanced, however, that the eggs were to be found on the 
shoots. Painting the rods with the winter alkali wash 
in the spring and a fumigation before the bloom 
appears to have been decided upon. 
A conservatory of 300 cubic feet, containing mixed 
flowers and ornamental plants and ferns, etc., infested 
with aphis and mealy bug was fumigated after sunset 
with cyanide, 8 ounces; acid, 12 ounces; water, 20 
ounces. ‘The temperature was 50° F. Time of ex- 
posure was three-quarters of an hour, with complete 
success. There was no injury to maidenhair fern 
or any of the plants under treatment. The cost did 
not exceed 1 shilling. 
A greenhouse of 2,000 cubic feet, containing chrys- 
anthemums in full bloom severely infested with green- 
fly, was treated one hour before sunset with cyanide, 
3% ounces (0.05 gramme per cubic foot); acid, 5 
ounces; water, g ounces. The temperature was 52° 
F. and the time of exposure was 25 minutes. Every 
aphis was killed, also slugs, flies, wasps and butter- 
flies. A toad was uninjured. Nota petal or leaf was 
hurt. 
Conclusions.—Mr. Cousins is of the opinion that 
these experiments should encourage practical men to 
give cyanide fumigation a thorough trial for such 
pests as are beyond ordinary treatment. For green- 
house work he recommends the following: If the 
house be under 10,000 cubic feet one vessel will suffice; 
if over, provide a vessel for each 10,000 cubic feet. 
Arrange the ventilators so that they can be opened 
