150 Cockroaches, Locusts, Grasshoppers, and Crickets 
The katydids are rather large, almost always green insects that live in 
trees and shrubs, where they feed upon the leaves and tender twigs, some¬ 
times doing considerable injury. With almost all the other Locustids, 
they will also take animal food if accessible, and some of the ground- 
inhabiting forms undoubtedly depend largely on animal substances for 
food. The color and form of the wing-covers and body serve to make them 
nearly indistinguishable in the foliage, and as they do not flock together 
in numbers, they are not frequently seen. Their love-calls or songs, how¬ 
ever, make the welkin ring at night from 
midsummer until the coming of frost. Few 
katydids sing by day: it would bring their 
enemies, the birds, down on them; but as 
twilight approaches, the males begin their 
shrilling, which is kept up almost constantly 
till daylight. Like the sound-making Acri- 
diids the musical Locustids have a pair of 
special auditory organs, or ears, for hearing 
these love-songs. These ears are tympanal 
organs situated one in the base of each fore 
tibia (the Acridiid ears are on the upper 
part of the first abdominal segment), and 
consist of a thin place in the chitinized 
body-wall (the tympanum), a resonance- 
chamber inside, and a special arrangement 
of nerves and ganglia. There are several 
genera of these Locustids, corresponding to 
the distinctions popularly made under the 
vernacular names narrow-winged, round¬ 
winged, angular-winged, oblong leaf-winged, 
and broad-winged katydids. The true 
katydid is one of the last-named forms, 
the commonest and most wide-spread species 
being Crytophyllus concavus . (Fig. 200). 
It is bright dark-green, and is rarely 
distinguished when at rest in the foliage, although familiar to all from its 
shrill singing. When specimens of katydids are collected and examined, 
concavus may be readily distinguished by the fact that its wings are shorter 
than the wing-covers, and these latter are very convex and so curved around 
the body that their edges meet above and below. The ovipositor of the 
female is short, compressed, slightly curved and pointed. This katydid 
is most in evidence in late summer. People disagree about the melody 
and alleged charm of the song. Many cannot distinguish the “katydid” 
Fig. 200.—Broad-winged katydid, 
Cyrtophyllus concavus , male. 
(After Harris; natural size.) 
