27 



mentioned were uttered by both forms of the insect found here, and 

 were so nearly alike that that uttered by either species, could not be 

 distinguished from similar sounds of its relative. I was somewhat sur- 

 prised at this. The difference in the size of the insects and therewith 

 in the size of the sound organs and ot* the controlling muscles should, 

 I thought, indicate a difference in the sound produced. In the third 

 distinct sound, that in which the males display their musical charms to 

 the other sex, I found a difference which, in all the investigations I 

 made,. proved constant. The note of the varietal form is uttered with- 

 out much change of tone and, individually, is quite low compared with 

 that of the other form, but collectively the noise, when the observer is 

 near, sounds like the rushing of a strong wind through trees of dense 

 foliage. I have distinguished this sound at a distance of a quarter of 

 a mile from the place of its origin, and at that distance it sounded like 

 the noise made by a swarm of bees passing through the air close at 

 baud. The sound made by the specific form is so peculiar as to at 

 once attract attention. It is uttered in an uncertain quivering way, 

 gradually rising, then falling and passing away as though ended by 

 the exhaustion of the insect. This souud is well represented thus: 

 Fe-e-e-ro-o-o. My friend, M. J. F. McKee, whose valued assistance I 

 have had in preparing my notes on the Cicada, watched the action of this 

 insect in giving utterance to this sound. He says: "The male Cicada 

 (C. septendecim) assumes a position on the upper side of a limb ir ou 

 the body of a tree, always with the head upward, then T 't elevates the 

 posterior enu of its body, at the same time appearing to inflate the 

 abdomen. With the beginning of the sound the elevated portion of the 

 body descends, the abdomen appears to contract until, when the parts 

 reach their natural position, the notes cease. The insect then remains 

 quiet for a period about equal to the length of the musical effort, Avhen 

 the performance is repeated. A noise may be produced from a freshly- 

 killed male by taking hold of each end of the body with one's fingers, 

 and alternately expanding and contracting the abdomen, similar to the 

 manner in which an accordion is played. The souuds thus produced 

 are not similar to those produced by the insect itself, but in many par- 

 ticulars there is a decided resemblance, and this, I think, demonstrates 

 the manner in which the sounds are produced." Evidently this is done 

 by inflating the hollow abdomen with air, and then forcing the air 

 against the corrugated surface of the insect's drum-like membranes, 

 when, by the vibration of these membranes as permitted by the power- 

 ful muscles attached thereto, the noise is produced. I have not been 

 enabled to make as satisfactory an examination of variety cassinii when 

 uttering its sounds. They are evidently produced in a similar manner, 

 but the motions occurring are different, a trembling of the posterior 

 parts being all that 1 have discovered. 



Toward the latter part of their lives the Cicadas appear to be affected 

 by a peculiar fungus growth. This is most common to the males, but 



