108 
THE PERIODICAL CICADA. 
It is, nevertheless, important to know what may be done in the way of 
protection and control whenever occasion arises to make snch action 
necessary, as for the protection of young- fruit trees which are especially 
exposed to injury or trees and shrubs over limited areas, as in parks 
and lawns. 
Precautionary operations are necessarily against the adults chiefly, 
as being the authors of the greater damage. Against the larvae and 
pupae in their subterranean life it is hardly worth while to take any 
action unless it be deemed desirable to attempt to exterminate a brood 
within a given territory or bit of woodland, in which case the remedies 
commonly employed against other subterranean insects, such as the 
Phylloxera or other root lice, will serve for this insect equally well, espe- 
cially in the first year or two of its existence. 
MEANS OF DESTROYING THE EMERGED PTJP^ AND ADULTS. 
Two methods of control suggest themselves against the adult insect, 
namely, (1) the killing of the insects by direct applications or mechan- 
ical means; and (2) the adoption of steps to deter or prevent the female 
from ovipositing on treated or protected plants. 
All efforts in the latter direction have proved unavailing, with the 
exception of mechanical precautious, which may be applied to small 
trees and shrubs, such as covering them with netting or the continual 
driving of the insect from the plants by beating or collecting them in 
umbrellas or bags in the early morning or late in the evening, when 
they are somewhat torpid and sluggish. 
All sorts of repellant substances applied as washes to trees have 
proved unavailing. Many experiments in this direction were made by 
Professor Riley in 1868, and later, at his instance, by Dr. W. S. Barnard, 
who tried wetting the trees with kerosene emulsions in different 
strengths, with various oils, and with carbolic acid solutions, etc., all 
most pungent and disagreeably smelling substances, with results either 
unsatisfactory or of negative value. 
Various treatments aiming at the destruction of the insects them- 
selves have yielded more satisfactory results, but to have any practical 
value it is necessary to continue them daily or as long as the insects 
issue in any numbers. On a large scale, therefore, or over a consider- 
able territory, in the presence of immense swarms, work of this sort 
will be ordinarily out of the questiou. The recommendations apply 
particularly, therefore, to small areas or orchards. Such work may be 
directed against the Cicada the moment it emerges from the ground, 
while still in the pupal stage, but perhaps more readily and success- 
fully against the insect after it has shed its pupal skin and is still 
soft and comparatively helpless, and with less ease, but still with 
some degree of effectiveness, after it has hardened and begun its aerial 
duties. 
If undertaken at the first appearance of the Cicada and repeated 
