70 



invariably three and almost never four — sounding like chic-a-chee, repeated rapidly so as 

 to be almost confounded, and when three requiring just one-third of a second ; the song is 

 repeated at will, generally once in about five seconds for an indefinite length of time. 



Microcentrum laurifolium (Linn.) McNeill says the note of this grasshopper 

 *' may be represented by the syllable tic repeated from eight to twenty times at the rate 

 of about four to the second." 



Microcentrum retinervis (Burm). Fig. 45. Riley gives an admirable account of this 

 insect in his Sixth Missouri Report, from which the following statement regarding its song 

 is taken : 



" 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 partly opened by a 

 sudden jerk, and the notes produced by a 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 universally 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." 



" Both sexes are for the most part silent during the day, but during the period of 

 their greatest activity their stridulations are never for an hour remitted, from the time 

 the great setting sun hides behind the purple curtains of the west till he begins to shed 

 his scarlet rays in the east — the species being so numerous that the sound as it comes 



from the woods is one continuous rattling, not unlike the 

 croaking of the frog, but set to a higher key. • • 

 I have noticed no particular difference in the day and 

 night note, except in the greater intensity of the latter." 



Davis says of the same species that it " produces 

 two somewhat diiferent songs, or perhaps more correctly, 

 varies the same song in time or extent of utterance, so 

 that unless the same individual is listened to for some 

 time, the notes might be attributed to different species," 



Cyrtophyllus concavus (Harr. ) Since 1 began to study 

 the character of the notes produced by different species 

 of Orthoptera, it has been my fortune to hear that of this 

 the true katydid (Fig. 46) but once or twice. This 

 insect lives in tree tops, one or two only in a tree, in 

 little colonies scattered here and there over most of the 

 United States east of the Rocky Mountains. One such 

 colon}'' I encountered in the heart of the city of Spring- 

 field, Mass., and spent an evening endeavoring to reduce 

 the notes to scale. The insects which I observed were 

 from fifteen to twenty rods distant, perched in the tops 

 of maple, jherry and elm trees, not far above my window. 

 They ordinarily call " Katy," or say " She did " rather 

 than " Katy did;" that is, they rasp their fore wings 

 twice, more frequently than thrice ; thnse two notes are 

 of equal (and extraordinary) emphasis, the latter about 

 one-quarter longer than the former ; or, if three notes 

 are given, the first and second are alike and a little 

 shorter than the last ; the notes are repeated at the rate 

 of two hundred per minute ; and while the interval 

 between two series of notes varies to a certain degree, it is seldom greater than two and 

 one-third seconds, or less than a second and a quarter ; usually it is between one and 

 seven-eishths and two seconds. 



Fig. 46. 



