INSECTS. 



321 



male. The males of this species {Pachytyliis migratorius) 

 while coupled with the female stridulate from anger or 

 jealousy if approached by other males. The house-cricket 

 when surprised at night uses its voice to warn its fellows. 'Q 

 In North America the Katydid {Ptatyphyllum concavum, 

 one of the Locustidae) is described f as mounting on the 

 upi>er branches of a tree, and in the evening beginning 

 **his noisy babble, while rival notes issue from the neigh- 

 boring ti-ees, and the groves resound with the call of 

 Katy - did - she - did the live- 

 long night." Mr. Bates, in 

 speaking of the European 

 field-cricket (one of the Ache- 

 tidae), says ^^the male has been 

 observed to place himself in 

 the evening at the entrance 

 of his burrow, and stridulate 

 until a female approaches, 

 when the louder notes are 

 succeeded by a more subdued 

 tone, while the successful 

 musician caresses with his 

 antennae the mate he has 

 won. "J Dr. Scudder was able 

 to excite one of these insects 

 to answer him, by rubbing on 

 a file with a quill. In both 

 sexes a remarkable auditory 

 apparatus has been discovered 

 by Von Siebold, situated in the front legs. || 



In the three families the sounds are differently produced. 

 In the males of the Achetidae both wing-covers have the 

 same apparatus; and this in the field-cricket (Gryllus 

 campestris, fig. 11) consists, as described by Landois,!^ of 



Gilbert White, " Nat. Hist, of Selborne," vol. ii, 1825, p. 262. 



f Harris, " Insects of New England," 1842, p. 128. 



X" The Naturalist on the Amazons," vol. i. 1863, p. 252. Mr. 

 Bates gives a very interesting discussion on tlie gradations in the 

 musical apparatus of the three families. See also Westwood, ' ' Mod- 

 ern Class.," vol. ii, pp. 445, 453. 



" Proc. Boston Soc. of Nat. Hist.," vol. xi, April, 1868. 



( " Nouveau Manuel d'Anat. Comp." (French translat.), torn, i, 

 1850, p. 567. 



1" Zeitschrift fur wissenschaft. Zoolog.," B. xvii, 1867, s. 117. 



Fig. 



11. Gryllus campestris (from 

 Landois). 

 Right-hand figure, under side of part 

 of a wing-nervure, much magnified, 

 showing the teeth, st. 

 Left-hand figure, upper surface of 

 wing-cover, with the projecting, 

 smooth nervure, r, across which the 

 teeth {st) are scraped. 



