The Locustidae, notwithstanding the fact that their alar organs are generally more ample than those of the Acridiidae, seem to be, as a rule, of more sedentary habits, and more nocturnal in their activity. The musical powers of the different species are very varied. _Locusta viridissima_ produces a shrill and monotonous but not disagreeable, sound, and is capable of sustaining it for a quarter of an hour without any intermission, except a break for the sake of starting again immediately with greater force, like a performer on a flute. It occasionally chirps in the day, but the act is then very brief. Bates informs us that one of these singing grasshoppers, called Tananá by the natives of the Amazon valley, is much admired for its singing, and is kept in little cages. The Amazonian naturalist thought the music of this species superior to that of any other Orthopterous Insect he had heard. The name of this grasshopper is _Thliboscelus camellifolius_. It is very similar in appearance to _Cyrtophyllus crepitans_, the Insect we have represented in Fig. 187. [Illustration: FIG. 195.—Inner face of base of tegmina of _Locusta viridissima_: A, the two wing-covers separated; B, in natural position with mesonotum connecting them, showing file and edge scraping it; _a_, the stridulating file; _b_, the rudimentary file on other tegmen.] The most notorious of the musical Locustids are the Katydids {320}of North America. There are several species of them—they belong, indeed, to more than one genus,—but it seems that sounds somewhat resembling the words Katy-did are perceptible in most of their performances. These sounds are frequently repeated with slight variations—Katy-did, O-she-did, Katy-did-she-did. Riley describes the music of the Katydid we represent in Fig. 196 as follows:[249] "The first notes from this Katydid are heard about the middle of July, and the species is in full song by the first of August. The wing-covers are partially opened by a sudden jerk, and the notes produced by the gradual closing of the same. The song consists of a series of from twenty-five to thirty raspings, as of a stiff quill drawn across a coarse file. There are about five of these raspings or trills per second, all alike, and with equal intervals, except the last two or three, which, with the closing of the wing-covers, run into each other. The whole strongly recalls the slow turning of a child's wooden rattle, ending by a sudden jerk of the same; and this prolonged rattling, which is peculiar to the male, is invariably and instantly answered by a single sharp 'chirp' or 'tschick' from one or more females, who produce the sound by a sudden upward jerk of the wings." [Illustration: FIG. 196.—Katydid, _Microcentrum retinerve_. N. America. (After Riley.)]