138 FUMIGATION METHODS 



in fruit, ferns, palms, and a large variety of general 

 stove plants. Not only*were the mealy bugs, scales, 

 and aphides destroyed, but a large per cent, of sow 

 bugs were found dead on the walks and under the moss 

 which covered the floor of the solid bed in the stove- 

 room. Even the earthworms on the surface of the soil 

 under the moss were dead. 



Another house containing 22,729 cubic feet of space 

 was fumigated, using one ounce potassium cyanide to 

 every 285 cubic feet. It contained carnations, smilax, 

 violets, coleus, chrysanthemums, small lettuce, cut- 

 tings, and small plants of bedded stock. It was in- 

 fested with the common mealy bug, Dactylopius de- 

 structor, green fly, and the white-tailed mealy bug, 

 Orthezia insignis. It was fumigated for thirty min- 

 utes upon a cloudy morning, yet in daylight. The in- 

 sects were mostly killed, but some of the plants were 

 badly injured. This was especially true in case of the 

 smilax, the upper leaves of carnations and lettuce. 

 Much of the latter, which was very small and in full 

 light, was killed, while some that was shaded showed 

 much less injury. The smilax and carnations recov- 

 ered in time, but received a severe check. Smilax and 

 more delicate plants have been subjected to double 

 this strength of gas by the writer, in darkness, without 

 injury. 



About the middle of January a camellia-room was 

 fumigated with one ounce potassium cyanide to every 

 3,000 cubic feet. The room contained 6,196 cubic feet, 

 and 2.06 ounces cyanide were used. It was fumigated 

 at night about six o'clock, and remained closed until 

 morning. 



