178 THE CAUSES WHICH PUOP AGATE 



repeats it a certain number o£ times, as many as twenty-five, 

 with intervals of about a second. When the male encounters a 

 female, even, it is said, should she be of a different species, he 

 suddenly stops, directs to her his antennae, and approaches as 

 near as possible. This insect and canine formality being com- 

 pleted, he then commences to stridulate almost insensibly, and 

 Avill continue his snatches for as many as a hundred times. 

 The female the while usually remains immovable ; but should she, 

 on the contrary, move off, she is then followed by the male, who, 

 if he lose sight of her, sounds the note " tzin,^^ and seeks about 

 until he meets with other males or a female. The former partake 

 in his uneasiness, reply with the same note, and join in the chase ; 

 but if disconcerted, and one should resume the ordinary music, 

 the others flag and similarly reply. 



If this species has a superficial resemblance to our common 

 large green grasshopper, another {8tenobothrn8 stigmaticus, 

 Rambur) has decidedly the form of S. pratorum, with the colour- 

 pattern of S. lineatus. In the cabinet it may be discriminated 

 by a slight difference in venation, it is said, and by the struc- 

 ture of the antennae, though to a more superficial observer, 

 perhaps, the green slash down the upper side of the femora and 

 the distinguishable black spots on the elytra will afford the 

 most tangible points. In its hardy habits and music, however, 

 it is quite distinct ; and in Piedmont, where I have myself 

 listened to the males stridulatiug, its dashing " Whir, whir-he- 

 wee " constitutes one of the chief charms of the alluvial 

 meadows. This singular challenge, which I have even caused 

 an over-heedy individual to reply to in the hay-fields by whistling 

 in imitation, usually lasts some fifteen seconds, and is produced by 

 some four femoral strokes ; but, as with other grasshoppers, during 

 its reproductive season in September, when engaged in soliciting 

 his female, a shorter and harsher pairing note is adopted, pro- 

 duced by a grating stroke from one or both hind legs — a sound 

 nevertheless as carefully attuned to vibrate through the female 

 chords of sense, as the brisker notes that are thrown out to 

 exasperate his fellows. 



In a few grasshoppers we find the keels on the pronotum 

 parallel. Stenohothrus elegans, one of these kinds, rare in this 

 country, has a note first heard in June, which lasts from half a 



