240 KEPORT OF THE COMMISSIONER OF AGRICULTURE. 



tion, that it was the counterpart of that made by QScanthiis latipennis, 

 Eiley, late in autumn, and when shortened from age and debility of the 

 stridulator. 



" Second. The loudest note, and the one which is undoubtedly most 

 identified with the species in the popular miud, is what may be called 

 the ' screech.' This is the note described by Fitch as ' represented by 

 the letters tsh-e-e-E-E-E-E-E-e-ou^ uttered continuously, and prolonged 

 to a quarter or half a minute in length, the middle of the note being 

 deafeniugJy shrill, loud, and i)iercing to the ear, and its termination 

 gradually lowered till the sound expires.' Dr. Fitch errs as to the 

 length of its duration; and I have also erred in the same direction, uu- 

 Tess, indeed, there is a still greater range than my subsequent observa- 

 tions would indicate.* It is more probable, however, that our memories 

 were at fault; for, as I have verified this year, this shrilling ordinarily lasts 

 from two to three seconds, though occasionally longer, and is repeated 

 at intervals of every five seconds. This note is rarely made by solitary 

 males, or when but few are gathered together ; but it is the prevailing 

 note in the height of the season, and is made in unison; i. e., the as- 

 sembled males on a given tree, or witLin a given grove, are prompted to 

 it simultaneously, so that its intensity becomes almost deafening at 

 times. It is of the same nature as that made by the Dog-day Cicada 

 {Cicada pruinosa, Say), and in its higher and louder soundings is not 

 unlike the shrilling of that species, though by no means so sharp and 

 continuous. It is what in the distance gives the threshing-machine 

 sound, and it has often recalled what I have heard in a saw-mill when 

 a log is being cut crosswise by a circular saw. 



" Third. There is what may be called the intermittent, chirping sound, 

 which consists of a series of from fifteen to thirty, but usually about 

 twenty-two, sharp notes, sometimes double, lasting in the aggregate 

 about five seconds. This sound is so much like that ordinarily pi<- 

 duced by the barn or chimney swallow {Hirundo crythrogaster), that a 

 description of the one would answer fairly well for botlu It resembles 

 also, though clearer and of higher pitch, the note of Microccnirum reti- 

 nerve, Burm., which I have likened to the slow turning of a child's 

 wooden rattle highly pitched. The above notes, so far as I have recog- 

 nized them, are of higher pitch, but of less volume, in the smaller cas- 

 sinn form. 



"The other notes — viz, that made when the insect is disturbed; and 

 a not infrequent, short cry, that may be likened to that of a chick — are 

 comparatively unimportant; but no one could do justice to the notes 

 of this insect without embracing the three peculiar sounds which I 

 have attempted to describe above, and which are commingled in tlie 

 woods where the species is at all, common; though tbe undulatory 

 screech is by far the most intense and most likely to be remembered." 



VARIATION IN TIME OF AFPEARANCE. 



It has long been known and well established that a few precursors 

 may appear the year before, and a few belated individuals tbe year 

 after, the regular appearance of any large brood. The exact cause or 

 causes for this exceptional variation in the development of a species 

 which shows, on the whole, such remarkable uniformity in its life-his- 

 tory has not been definitely ascertained. The presumption is, however, 



* " Since tliia waa -written, I have hoard, on two occasions, this note prolonged to 

 twenty seconds; hut this is quite abnormal, and I have no other evidence than the 

 season (Juno 20) to prove that it came from C. septentlecim." 



