THE SENSES OF INSECTS. 



29 



an extremely delicate vesicle (bi) filled with a transparent 

 fluid, and representing a membranous labyrinth. This 

 vesicle is in connection with an auditory nerve (n) which 



FIG. 22. Ear of a locust (Culoptenus itulicus). seen fiom the inner side. T, 

 tympanum; TR, its border; o, u, two horn-like processes; 6f, pear-shaped 

 vesicle; n, auditory nerve: ga, terminal ganglion; st, stigma; m, opening, and 

 m' closing, muscle of the same: M, tensor muscle of the tympanum-mein- 

 brane. After Graber. 



CM- 



FIG. a3. I, fore tibia of a European grasshopper (Meconema), containing tin. 

 ear: Ty, tympanum or outer membrane: 7V1, 7Y2, trachea. II, diagram- 

 matic cross-section through the tibia and e;ir of the same: Ty, tympanum; 

 Ct, cuticula; CM, hypodermis; A. the auditors organ connecting with the 

 tympanum; B, supra-tympanal auditory organ ; (*Z, the ganglion-cell belong- 

 ing to them; Hst, the auditory rod connecting with the ganglion-cells After 

 draber, from Judeich and Nltsche. 



