The Crickets 



descriptive names are applied to it in many foreign tongues. Tiie 

 common field crickets (Gryllus neglectus, for example^ are often 

 very musical at night. Scudder says that sometimes the notes 

 are produced as slowly as two per second, but that they may be 

 twice as rapid. The note is a shrill one, and is said to be 

 pitched at e natural, two octaves above middle c. It is recorded 

 as follows : 



cnri crrri crrri cnrl crrrl 



Fig. 232. — Song of the field cricket. (After Scudder.) 



Perhaps the commonest night song, however, is that of the 

 snowy tree cricket (CEcanthus niveiis et al). The notes of our 

 three or four species of snowy tree crickets vary much in intensity. 

 There is a distinct relation between the temperature and the 

 number of notes per minute. Professor Dolbear has reduced this 

 to a mathematical formula. He says: 



Let T = temperature in degrees Fahrenheit; N = number of 

 chirps per minute. Then T = 50 +^-40^ This would give 100 

 chirps for 65 degrees Fahrenheit. 



This formula has been tested in Massachusetts by Dr. Robert 

 Edes and Mr. Walter Faxon, who find that from actual records 

 the temperature is about 6} degrees to 100 chirps, with an error of 

 variation of one degree or less in four-fifths of the cases. The 

 day song is annotated by Mr. Scudder as follows, and he states 

 that it is a nearly uniform, equally-sustained trill lasting from two or 

 three seconds to a minute or two. The insect, however, "often 

 begins its note at a different pitch from the normal one — fourth y 

 above middle c — as if it required a little practice to attain it." 



TTJTbl b b b c^ b bifbTbTb b b "ITrb b b b 



Fig. 233. — Day song of a snowy tree cricket. (After Scudder.) 



The song of Qlcanthus niveus is by far the most famil- 

 iar one. Riley gave the best description of it when he said 

 that it "is intermittent, resembling a shrill 're-teat, re-teat, 



343 



