252 THE FLORIST AND 
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 atmosphere sinks below a certain point. Having noticed this fact at 
different 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 ther- 
mometer, 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 in 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. 
It may be further remarked that they hasten their time just in proportion 
as they raise their key, and that they likewise sing both in better time and 
better tune, in proportion to the warmth of the weather. When the mercury 
stood at 80°, I was never able to detect a single insect performing out of 
time or tune. The whole myriad choir were singing in perfect harmony; 
their key being about F natural, and their time about three notes to a 
second, which is very rapid. During this high temperature, the shriller 
toned insects, as the diurnal grasshoppers and the black crickets, sing in 
unison with the August pipers, varying their tone in the same manner with 
the variations of temperature. But the diurnal insects do not keep time so 
weH as those which are the particular subject of my observations. 
When the niercury stands at about 70°, a few insects may be heard singing 
out of tune. Their time is also ro.ore imperfect, and is equal to about two 
notes to a second. When the weather is as cold as 60° — the average tern- 
