INSECT MUSICIANS SNODGRASS 439 



tensity that there can be no mistaking the source of its origin, and 

 right there in plain sight on a leaf sits a little, delicate, slim-legged, 

 pale green insect with hazy transparent sails outspread above its 

 back. But can such an insignificant creature be making such a 

 deafening sound ! It has required very cautious tactics to have ap- 

 proached thus close without stopping the music, and it needs but 

 a touch on stem or leaf to make it cease. But now those gauzy 

 sails that before were a blurred vignette have acquired a definite 

 outline, and a little more disturbance may cause them to be lowered 

 and spread flat on the creature's back. The music will not begin 

 anew until you have passed a period of silent waiting. Then sud- 

 denly those lacy films go up, once more their outlines blurr, and that 

 intense scream again pierces your ear. In short, you are witness- 

 ing a private performance of the broad-winged tree cricket, 

 Oecanthus latipennis. 



But if you pay attention to the notes of other singers you will 

 observe that there is a variety of airs in the medley going on. 

 Many others are long trills like the one just identified, lasting in- 

 definitely, but others are softer, purring notes about two seconds 

 in length, while still others are short beats repeated regularly a 

 hundred or more times every minute. The last are the notes of the 

 snowy tree cricket, Oecanthus niveus, so-called on account of his 

 paleness. He is really green in color, but a green of such a very 

 pale shade that he looks almost white in the dark. The male (fig. 

 23) is a little longer than half an inch, his wings are wide and flat, 

 overlapping when folded on the back, with the edges turned down 

 against the sides of the body. The female is heavier bodied than 

 the male, but her wings are narrow and when folded are furled 

 along the back. She has a long ovipositor for inserting her eggs into 

 the bark of trees. 



The males of the snowy cricket reach maturity and begin to sing 

 about the middle of July. The singer raises his wings vertically 

 above the back and vibrates them sideways so rapidly that they are 

 momentarily blurred with each note. The sound is that treat, treat, 

 treat, treat already described, repeated regularly, rhythmically, and 

 monotonously all through the night. At the first of the season there 

 may be about 125 beats every minute, but later, on hot nights, the 

 strokes become more rapid and mount to 160 a minute. In the fall 

 again the rate decreases on cool evenings to perhaps a 100. And 

 finally, at the end of the season, when the players are benumbed 

 with cold, the notes become hoarse bleats repeated slowly and ir- 

 regularly as if produced with pain and difficulty. 



The several species of tree crickets belonging to the genus Oecan- 

 thus are similar in appearance, though the males differ somewhat 

 in the width of the wings and some species are more or less diffused 



