106 
determined, but in greenhouses the total life cycle usually requires 
two to three months. 
Remedial Measures .—Spraying with one of the arsenicals. 
preferably arsenate of lead—three pounds to fifty gallons of water 
—is perhaps the best method of dealing with this insect. The 
application must be thoro and the spray fine and mistlike, as it 
is essential to coat the foliage completely without wetting the soil 
unduly. This method is practicable, of course, either in green¬ 
houses or out-of-doors, but it will be found most satisfactory to 
Fig. 21. Aliernanthera Worm, //y* 
menta ferspectalis, adult. About twice 
natural size. 
spray the outdoor beds in summer, to destroy the early generations 
and thus prevent their multiplication and their introduction later 
to the greenhouses, where they become especially destructive to 
the small Alternanthera plants. 
Hand-picking is a valuable aid when plants are in pots in the 
greenhouse. 
Light traps (see p. 87) have proven of value. In the green¬ 
house where candle-light was used, twelve to eighteen moths were 
collected nightly in a single trap. While this method will not 
alone control the pest, it will be useful as an adjunct of hand¬ 
picking and spraying. 
The Rose Midge 
Neocerata rhodophaga Coq. 
The injury done by the maggots of the rose midge is quite 
characteristic. In summer, when development is rapid, they at¬ 
tack the very young flower or leaf-buds, preferably the former. 
Infested buds die, turning brownish or black (Fig. 22), and upon 
examination minute whitish maggots will be found within them, 
often as many as twenty or thirty in a single bud. W hen the 
maggots are not very abundant, and particularly in spring, when 
their growth and multiplication are slow, the larger flower-buds 
are more often attacked than later, the reason being that they 
have had a better chance to develop before being severely at¬ 
tacked. The bud in this case is disfigured and deformed as shown 
