9 
v0 
Adiantum cuneatum and A. Ballii have been tried on a small 
scale and were not injured by the treatment. 
Coleus.—‘' Golden Bedder,” ‘‘ Verchaffeltii,” ‘‘ Shylock,” and 
others. 24,000 plants in pots, badly infested with the ‘‘ white-tailed ” 
mealy bug (Orthezia insignis). The house contained 15,587 cubic 
feet of space. Treated at the rate of one-tenth of a gram of 98 per 
cent cyanide of potash per cubic foot of space for twenty minutes, 
one hour after dark. Orthezia all killed and plants not injured in 
the least. All other means of destroying the Orthezia had been tried 
without effect. Large numbers of the common mealy bug were also 
killed by this treatment; but it was not nearly so effective as for the 
‘ white-tailed” mealy bug. All coleus cuttings made by the United 
States Propagating Gardens for the past two years have been fumi- 
gated before being prepared for the cutting bed (see fig. 1). 
Double English violets.—** Marie Louise,” ‘‘Lady Campbell,” 
and others. For plant-lice and general fumigation. fifteen-hundredths 
of a gram of 98 per cent cyanide of potash for each cubic foot of 
space is required. The exposure, if made according to directions, 
will not hurt the plants in any stage of growth. The gas has been 
used on a large scale in fumigating violets for the past three years 
with the greatest success, only a few treatments during the season 
being required. Leaf-eating larvee, slugs, millipedes, cutworms, etc., 
when exposed are killed as well as plant-lice. Red spiders, however, 
are not entirely eradicated by the treatment. The foliage of single 
violets like California and Princess of Wales are sometimes slightly 
injured by the stronger dose of gas. A weaker dose (one-tenth of a 
gram potassium cyanide per cubic foot) should be used when they 
are to be treated. 
Other plants.—Other plants on which the gas has been tried on 
a small scale indicate that it may probably have quite a wide range 
of usefulness. * 
Roses. —‘** Perle des jardins,” ‘‘ Mermet,” and ‘‘ Bride.” The 
young growth on roses is particularly sensitive and has been more 
or less injured in all our experiments. 
Carnations.—Scott, Garfield, Meteor, and McGowan will stand 
one-tenth of a gram 98 per cent oy anide per cubic foot of signa for 
é The gas has nee eal on fe Pepe plants at the rate of one- fon gram 
of cyanide per cubic foot of space for twenty minutes without injury. Further 
experiment, however, is necessary before the treatment can be recommended 
for these: Alocasia Macrorhiza variegata; Anthurium erystallinum ; Areca lutes- 
cens; Aralia filicifolia ; Adiantum cuneatum ; Adiantum Ballii ; Campylobotrys 
refulgens ; Cissus discolor; Crotons (in variety); Cichorium intybus ; Diffen- 
bachia Lenmanii; Ficus elastica; Fuchsias (in variety); Jacaranda mimose- 
folia ; Marantas (in variety); Nympheea candidissima, and odorata rosea ; Ponte- 
deria crassipes ; Pandanus veitchit ; Phrynium variegatum ; Phyllotcenium Lin- 
denii; Panax Victoric ; Stenanthium Lindenii. 
