356 ENTOMOLOGICAL NEWS [Oct., 'lO 



vironment of certain species. After the luxuriant vegetation 

 of the lowlands and marshes has become brown and withered, 

 the species of Conocephalus and the noisy Orchelimums are 

 no longer heard. When the forests have become bare, the trees 

 have lost not only their leaves, but also all the arboreal katydids 

 whose dwelling places were among the leaves. 



Unlike the warm summer nights which are enlivened with 

 the music and harmony of countless singing- musicians con- 

 cealed everywhere amidst the grasses, shrubs and trees, the 

 long, freezing, late autumn nights in New England, except for 

 the occasional wintry rustle of dry leaves, are painfully silent. 

 Not until the morning sun has become high, and the open fields 

 have lost their frosty chill, is there any sign of surviving insect 

 life. By midday, if the weather is mild, the hardier locusts 

 make their usual flights across the fields, and countless num- 

 bers of big and little crickets move restlessly about, trilling 

 ceaselessly in the grass until sundown. If the evening is very 

 warm, the slowly uttered trills of an occasional Oecanthus ni- 

 veus may sometimes be heard, yet how impressive and pathetic 

 these few short trills with their autumn environment of almost 

 leafless trees and shrubs ! 



The notes of Orthoptera at different times during the day 

 and at different seasons, show considerable variation in pitch, 

 intensity, sound-quality, and delivery. These differences are 

 mainly dependent upon varying conditions of moisture, tem- 

 perature, etc. Late in the night, after the air has become damp 

 and chilled, the deep-toned trill of Oecanthus lati[>cnnis is con- 

 siderably lower in pitch and intensity than the same trill heard 

 during warm afternoon hours. In the cool night air the wing 

 vibrations have slowed down, so that each successive note is 

 separated by longer intervals, imparting to the trill a marked 

 quaver or tone rhythm. Higher temperatures from day to 

 clay throughout the summer very quickly increase the tone in- 

 tensity and rate of delivery of the intermittent trills of Oecan- 

 thus niveus. In the same manner the colder temperatures of 

 late autumn markedly modify the intensity and delivery of the 

 notes of musical insects, until they become barely audible at 

 certain low temperatures. 



