20 BULLETIN 256, U. S. DEPARTMENT OP AGRICULTURE. 
the course of life, and in the orchard under normal conditions they 
probably deposit more than the maximum number here given, since 
on one occasion 133 eggs, showing advanced development, were re- 
moved from the ovisac of a female which had not oviposited during 
her entire life in captivity. The number of eggs laid at one time 
varied from 3 to 28. The adults live from three to three and one- 
half months, and are present in the orchard almost continuously 
from the middle of August to the middle of November. Adults lived 
in screen cages from 85 to 111 days. 
Seasonal History. 
Most of the eggs of this species are deposited during September and 
October, and all eggs secured from females in captivity in 1911 and 
1912 were deposited between September 4 and October 29. The 
eggs hatching the following spring, the nymphs make their appearance 
about the first of May. They reach the maximum abundance be- 
tween May 15 and July 15 and will seldom be seen after the middle of 
August. Adults are most numerous during the period from August 
15 to October 15; they are scarce in November and rare in December, 
finally disappearing entirely in January. 
CONTROL OF KATYDIDS ON ORANGES. 
Several methods have been suggested for the control of katydids on 
oranges, among which the following have been found to be imprac- 
tical: Destroying the nymphs by hand; gathering by hand and 
destroying the eggs; poisoning by the use of trap crops or by poisoned 
baits. It would be extremely difficult, if not impossible, to find any 
large percentage of eggs or nymphs, and the method would certainly 
prove too slow and tedious. The katydids can not be attracted from 
the fruit and foliage of the orange by any crop or bait while such an 
abundance of food so much to their liking is always at hand. Unless 
practically forced to quit the orange tree, they spend their entire lives 
upon the tree on which they are born. 
SPRAYING EXPERIMENTS. 
Spraying with arsenicals is generally considered to be impractical 
for the control of grasshoppers and locusts because of the large dose 
necessary to kill these robust insects and the difficulty of applying 
such a dose evenly and with safety to the trees. These objections 
would doubtless hold with the citrus katydids if the spraying were 
done after the insects had reached an advanced nymphal or the adult 
stage. They do not hold, however, when the trees are properly 
sprayed while the insects are still largely in the first, second, or third 
nymphal instars. 
