SEPTEMB!^>R. 433 



sensation of subdued but cheerful melancholy. This effect 

 does not seem to be the result of association so much as that 

 of some peculiar cadence or modulation of the sound. 



I believe it has not been generally noticed, that the notes 

 of these insects are commonly in unison. These nocturnal 

 pipers are the loudest singers of our indigenous insects, and 

 their notes are almost invariably an octave lower than those 

 of the black crickets. It is also worthy of notice, that they 

 always vary their key-note, according to the temperature of 

 the atmosphere, within certain degrees. They are evidently 

 dependent on a certain amount of heat for their vivacity, and 

 become more or less torpid as the temperature of the atmos- 

 phere sinks below a certain point. Having noticed this 

 fact at diflerent times, I was induced to make a series of 

 exact observations a few years since, by noticing the height 

 of the mercury in Fahrenheit's thermometer, and at the 

 same time finding the key upon which these insects were 

 chirping. My observations were commenced early in August, 

 and carried through September, which was on that year as 

 hot as July. The following is a general statement of the 

 results. 



When the temperature of the weather is indicated at 80° 

 Fahrenheit, these insects will be found singing invariably as 

 high as the key of F natural. When the mercury stands at 

 75°, they sing one tone lower or thereabouts, and always 

 change from a higher to a lower key, as the air grows colder, 

 and the contrary as it grows warmer. Their notes will be 

 found to vary about one tone with every five degrees of 

 change in the weather, as marked by the thermometer. I 

 will add that I have never heard them singing on a higher key 

 than F, or on a lower key than G. The weather is seldom 

 warmer than 80° in the evening, and when it is colder than 

 60°, the insects always sing out of tune and time, and some 

 of them as low as G. A colder temperature than this 

 diminishes their vivacity, and silences a great many of the 

 performers ; but after they have become so torpid that the 

 vibrations of their wings would produce a sound lower than 

 G, they become silent. 



VOL. XXI. NO. IX. 55 



