472 On the Organs of Hearing in Insects. 



longitudinal line : and at the base of each is usually observ- 

 able a small spot similar to the others. The posterior half 

 of the suture is bordered with a whitish colour. The extre- 

 mity of the elytra is terminated by two small points. The 

 breast and sides of the abdomen are whitish and shining. — 

 The antennae are black ; the legs are of the same colour, and 

 the base of the thighs testaceous. 



It is noticed as being found in Vanikoro, but I have be- 

 fore me another specimen taken in the North of New Holland 

 by Mr. Cunningham. 



Flacq, Mauritius, April 30th, 1838. 



Art. III. On the Organs of Hearing in Insects. By Leonard 

 W. Clarke, Esq., Honorary Entomological Curator to the Royal 

 School of Medicine at Birmingham. 



" The organ of hearing is excited by vibrations or undulations of air, of 

 water, or of some solid medium, recurring at intervals, with different de- 

 grees of frequency. These impulses are received upon the tympanum, or 

 ear-drum, thence they are communicated to the acoustic nerve, and are fi- 

 nally transmitted to the brain." — Cuvier. 



In 1832, when Professor Rennie presumed to revive the 

 notion, — the " silly and absurd " supposition, — that the an- 

 tennae were the organs by which insects distinguished sound, 

 he was treated with contumely; — the idea was ridiculed with- 

 out any inquiry whatever ; — it was consigned to the " tomb 

 of the Capulets," and the "corroborating testimony of all 

 great naturalists " triumphed ; — the world was induced to be- 

 lieve as before, that insects use antennae as feelers, and not 

 as ears, " while the Professor for his pains was honoured with 

 the dunce's cap and bells- With this example before me it 

 may be asked whether I dare to revive the almost annihilated 

 idea ? I do, most certainly, though under different auspices, 

 and upon very different grounds. 



The first consideration is whether insects are cognisant of 

 sound or not. Most entomologists admit that they are, but 

 confess their ignorance of the locality of the organs of hear- 

 ing. Some have imagined the antennae to be these organs ; 

 hitherto this has been no more than supposition, and of course 

 imagination and theory have failed to convince the multitude. 

 Are the antennae adapted for conveying sound ? Is there any 

 liquid in them similar to that which Scarpa discovered to fill 

 the labyrinth of the human ear ? Are there a tympanum, au- 

 ditory nerves, and an opening or external orifice through which 

 the vibrations of the air may be conveyed, by means of the 

 acoustic nerve to the first cerebroid ? Is there anything in 



