30 



ENTOMOLOGY. 



arises from the third thoracic ganglion, forms a ganglion 

 (go) upon the tympanum, and terminates in the immediate 

 neighborhood of the labyrinth by a collection of cuneiform, 

 staff -like bodies, with very finely-pointed extremities (primi- 

 tive nerve-fibres?), which are surrounded by loosely aggre- 



FIG. 24. Musical apparatus of cricket, a. a, tracheal tube; b. rasp or ridge 

 bearing vibratory flanges; d, resonant surface, with ridges. 



gated ganglionic globules" (Siebold's "Anatomy of the In- 

 vertebrates"). In the green grasshoppers, katydids, and 

 their allies, the ears are situated on the fore legs (tibia?), 

 where these organs can be found after a careful search (Fig. 

 23). 



Having ears to hear, locusts, grasshoppers, katydids, a,nd 

 crickets are also very musical. One may sometimes see the 

 red-legged locust standing on the ground and rubbing one 

 leg against the folded wing, and a shrill chirruping noise 

 may be heard. The noise is 

 made by a row of dull spines 

 on the inside of the femur, 

 forming a rude file which 

 rasps the wing. Certain 

 grasshoppers, as the katy- 

 did and the crickets (Figs. 

 24, 25), have on the under 

 side of the uppermost of the 



fore wings a sort of file which FIG. 25. Enlarged view of the vibratory 



flanges seen at b', Fig. 24. This and 



rubs over a resonant surface, Fig. 19 after N. B. Pierce. 



like a drum's head. The file may be likened to the bow, and 



