75 



feather (Myriophyllum proserpinacoides), water hyacinth (Eickhornia 

 erassipes major), water poppy (Limnocharis humboldti), Cyperus alterni- 

 folius, Papyrus antiquorum, oxalis, orchids in variety, roses, callas, 

 ferns, New Zealand flax, cobaeas,caladiums, etc. 



Results. — Upon examination the next day aphides were found all 

 dead, although as yet not discolored, and remaining in theii places. 

 Of 11 mealy bugs examined, 6 were dead and 5 alive. There was no 

 injury to any plant; except to the young foliage of the roses, which 

 was burned. 



TRIAL VII. 



Conditions. — Date, January 28, 1899 ; place, second octagon room ; all 

 night 5 1 oz. of potash cyanide to each 3,000 cu. ft. ; 8.56 oz. of potassium 

 cyanide, 17.12 oz. water, and 12.84 oz. sulphuric acid required; insects: 

 aphides, mealy bugs, and beetles; plants present: ferns, callas, palms 

 in variety, agaves, aspidistras, inarantas, guavas, jasminums, loquat, 

 durantas, ficus, manettias, pleromas, bananas, cordylines, yuccas, 

 Solanum jasminoides, Cherokee and climbing perle roses, bamboo, 

 abutilons, eytisus, etc. 



Results. — Aphides were killed. On January 31, three days after 

 fumigating, the only injury to plants was the burniug of the tender 

 leaves on the climbing perle rose, the tender leaves of the Solanum jas- 

 minoides, which was just starting into growth, and the new fast- growing 

 shoots of Asparagus tenuissimus. The tender leaves of Ihe Cherokee 

 rose were slightly burned. Almost none of the bugs (at least none of 

 the old ones) were killed; of 10 examined, at least 9 were alive; the 

 temperature was rather low, however. 



TRIAL VIII. 



Conditions. — Date, January 28, 1899; place, first octagon room; all 

 night; 1 oz. potassium cyanide to each 3,000 cu. ft.; 9.44 oz. cyanide of 

 potash, 18.88 oz. water, and 14.16 oz. sulphuric acid used; insects : aphi- 

 des and mealy bugs; plants present: asparagus (plumosus, sprengeri, 

 and tenuissimus), palms, vincas, ferns, mosses, dracsenas, eupatoriums, 

 ipomoeas, ficus (elastica and religiosa), eytisus, begonias, inarantas, 

 manettia, aspidistras, cyperus, etc.; the temperature was below 55° F. 



Results. — Aphides were killed; but of 50 mealy bugs examined, 

 mostly adults, however, only 8 were killed. No plants were injured, 

 with the exception of the asparagus, which was sending out new and 

 very tender growth. 



TRIAL IX. 



Conditions. — Date, February 15, 16, and 17, 1899; place, second octa- 

 gon room ; left in all night 3 nights in succession; 1 oz. cyanide of potash 

 to each 3,000 cu. ft.; 8.5 oz. cyanide of potash, 17 oz. water, and 13 oz. 

 sulphuric acid used each night; temperature averaged about 569 F.; 

 the insects for which this trial was made were mealy bugs. 



