i 
ARTIFICIAL REMEDIES. 
Topical Applications to the Foliage. 
In Prof. Riley’s first account of the Colaspis larve, in his third 
report, he says: ‘‘The only way to prevent the ravages of the worm, 
which we yet know of, is so to protect newly set plants that the 
beetles will not get access to them. I have had no opportunity to 
make experiments, but it may turn out that some application to the 
ground or to the plant, such as ashes, soot, lime, or salt, will ward 
off the perfect beetle. The same remedies used in killing the Colo- 
rado Potato-beetle would also kill this species.” 
In discussing the Paria root-worms, Prof. Cook remarks: ‘“‘I feel 
certain that either Paris green or London purple would certainly 
destroy the beetles, if applied to the plants as we apply them to 
destroy the potato beetle or canker worm.” 
From Prof. Burrill, of the Industrial University, I learn that a 
small bed of strawberries on the University grounds was attacked 
by the beetles of Paria aterrima, that the leaves were dusted with 
Paris green, and that the beetles immediately disappeared, no fur- 
ther injury being done to the vines. There is good reason to sup- 
pose, consequently, that this remedy would prove effective, as far as 
the adult beetles of all these species are concerned, and would thus 
place a check, at least, upon the increase of the larve. Such appli- 
cations would of course not be permissible during the fruiting sea- 
son, and, fortunately, the adults of none of these species emerge 
until after the berries are picked. 
Whether it is their usual habit to remain in the fields until after 
their eggs are laid, escaping to other situations and resorting to 
other food plants only after this indispensable office has been per- 
formed, is a point of importance upon which we have as yet no 
knowledge. Fruit growers are agreed, however, as far as my in- 
formation goes, that the root-worms spread usually from old fields 
to new somewhat slowly, as if by a gradual progression from side 
to side; and if this be true, it is altogether likely that the common 
habit of all the species is to lay their eggs before dispersing gener- 
ally, and the practice of poisoning the adults in the field will be 
fairly effective as against the root-worms themselves. 
The time when the poison is to. be applied will of course depend 
largely upon the species by which the field is infested. If all three 
are present, it will be absolutely necessary that several repetitions 
of the treatment should be had, beginning in June, when the Scelo- 
dontas are emerging, and continuing until August, when Paria comes 
forth. If Colaspis only is present in the field, July will be the proper 
time to poison the plants*. There is a bare possibility that the 
leaves and ground might be sprinkled with substances which should 
serve to repel the adults in search of places for the deposit of their 
eggs, and Prof. Riley has thought it worth while to suggest ashes, 
soot, lime, or salt, for this purpose; but there is extremely little genuine 
experimental evidence of the effectiveness of measures of this class. 
* The arsenical poisons are now so well understood that it is hardly necessary to re- 
iterate the oft-repeated warning against their excessive use. They serve their purpose 
if highly diluted with dust or plaster, or suspended in large quantities of water; but even 
then they should not be used on the same ground year after year, without occasional 
change of crops. 
