THE FACULTY OF HEARING. 35: 





BY H. E. FRIPP, M.D. 



IN a paper read before the Society in March, 1877, I gave an 

 account of some researches on insect sounds, and on a 

 supposed organ of voice. On the present occasion I propose to 

 discuss the question of a hearing faculty in insects, and to describe 

 certain structures which have been generally acknowledged to be 

 an undoubted auditory organ. 



Some years ago I exhibited at one of our meetings a series of 

 microscopic preparations of the tympanal organs of Locusta vir^ and 

 Acheta dom^, and I also showed some drawings of the tympanal 

 organ of Acridiiim as an example of homologically different, though 

 physiologically accordant structure. Having since that time 

 occasionally renewed my study of these organs^ and become 

 acquainted with the more recent work of Dr. V. Graher in Vienna, 

 I am enabled to give a more complete account of them, and also of 

 the opinions held by those who are best acquainted with their 

 structural and physical characters. If time permit, I may also 

 mention some curious experiments — atrocities my hearers may 

 perhaps call them — which the Vienna professor performed with 



