4 INTRODUCTION. 



single filaments, sometimes furnished with bristles or 

 hairs, which give them a comb-like or feather-like 

 appearance ; now they are thickened at the bottom, 

 now at the top ; now the last joints are formed of 

 broad laminae or plates; they are usually attached to 

 the front of the head between the eyes. It is not 

 definitely known what is the use of the antennae, beyond 

 the fact that they are organs of touch, but as such 

 only play a subordinate part. It has been supposed by 

 some that they are organs of hearing. From the 

 researches of M. Lespds, Erichson, and Dr. J. B. Hicks, 

 it would appear that the antennae of insects are organs 

 of hearing ; it is said " they consist of a cell, sac, or 

 cavity filled with fluid, closed in from the air by a 

 membrane analogous to that which closes the foramen 

 ovale in the higher animals ; that this membrane is for 

 the most part thin and delicate, but often projects 

 above the surface, in either a hemispherical, conical, or 

 canoe-shaped, or even hair-like form, or variously 

 marked ; that the antennal nerve gives off branches 

 which come in contact with the inner wall of the sacs."* 

 On the other hand it is asserted that the antennce are 

 partly organs of smell ; on this point Mr. Lowne says, 

 " I believe myself that this is the organ of smell, 

 although I by no means consider the antennae of all 

 insects are necessarily olfactory organs. I think in 

 many instances they are merely feelers. Perhaps the 

 beautiful feather-like antennae of male moths are sexual 

 ornaments, although they may have special olfactory 

 organs connected with them ; and possibly the laminated 



* Trans. Lin. Soc. Vol. xxii,, pt. 4. 



