THE PERIODICAL CICADA
is repeated at intervals of from two to five seconds, and is given always as a solo by individuals sitting in the bushes or on lower branches of the trees. Males singing the Pharaoh song, therefore, are easily observed in the act of performing. With the beginning of each note, the singer lifts his abdomen to a rigid, horizontal position, thus opening the cavity beneath the lower drumheads and letting out the full volume of the sound. Toward the end of the note, the abdomen drops again to the usual somewhat sagging position, appearing thus to give the abrupt falling inflection at the close.
The grand choruses, by which the periodical cicada is chiefly known and remembered, are given by the fully matured males of the swarm, always high in the trees where the singers may seldom be closely observed while performing. The individual notes are prolonged bur-r-r-r- like sounds, repeated all day and day after day, but all single voices are blended and lost in the continuous hum of the multitude.
The fourth note of the larger form of the cicada is uttered by males when they appear to be surprised or frightened. On such occasions, as the insect darts away, he makes a loud, rough sound, and the same note is often uttered when a male is picked up or otherwise handled.
The notes of the small form of the seventeen-year race of the cicada have an entirely different character from those of his larger relative. The regular song of the little males much more resembles that of the annual summer cicadas, though it is not so long and is less continuous in tone. It opens with a feu, short chirps; then follows a series of strong, shrill sounds like zwing, zwing, zwing, and so on, closing again with a number of chirps. The whole song lasts about fifteen seconds. Several of these males kept in cages for observation sang this song repeatedly and no other. It is common out of doors, but always heard in solo, never in chorus. When handled
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