OKTHOPTEUA OF NOVA SCOTIA. PIERS. 207 



in various ways, by a sawing or rasping movement of parts 

 on each other, as follows: — (a) By rubbing a series of minute 

 elastic teeth situated near the lower margin of the inner 

 surface of the hind femur, against a roughened vein of the 

 wing-cover. This is done by raising and lowering the femur 

 while the insect is otherwise at rest. _ This fiddling method 

 is the one characteristic of most of the" subfamily Locustinoe 

 (Spine-l)reasted Locusts) and the subfamily Acridince (Ob- 

 lique-faced Spineless Locusts), "and may be readily observed 

 in the case of Chorthippus curtipennis. Such species stridu- 

 late or call only during the daytime and the note is not loud, 

 (b) By rubbing the under surface of the wing-cover against 

 the upper surface of the front margin of the hind wings. 

 This is performed only during flight, and in daytime, an I 

 is the usual method with the sound-producing members 

 of the subfamily (Ec/ipoc^mcB (Vertical-faced Spineless Locusts). 

 It pro'luces such notes as the cracking of Circotettix verru- 

 culatus. (c) By rubbing a particular vein or scraper-like 

 part at or near the base of one wing-cover, against a file-like 

 vein which crosses a resonant area at or near the base of 

 the other wing-cover. This is performed by night as 

 well as by day, by parting and closing the wing-covers while 

 the insect is otherwise at rest. It is the method employed, 

 with slight modifications as to the apparatus, by the sound- 

 producing members of the family Tettigoniidoe (Long-horned 

 Grasshoppers, omitting the silent Stone and Camel Crickets) 

 and the family Gri/llidce (Crickets). Familiar examples 

 are the strident call of the Katydids and the shrilling of the 

 Ground and Field Crickets. Interesting records of orthop- 

 teran call-notes, many reduced to musical notation, will 

 be found in two papers by Dr. S. H. Scudder, "Notes on 

 the Stridulation of Some New England Orthoptera" (Proc. 

 Bost. Soc. Nat. Hist., xi, 306-313, Bost., 1868) and "Songs 

 of Our Grasshoppers and Crickets" (Ann. Rep. Ent. Soc. 

 Ont., xxiii, 62-78, Toronto, 1893). 



