BONSDORF ON THE ANTENN/E OF INSECTS. 



297 



pared with our senses, nor to be confounded with any organ of insects 

 different from ours. This is the same as to maintain that the Divine 

 Artificer of the world is bound by definite laws, and that the model of 

 works in the universal series of animals is necessarily so uniform, that 

 with the dissimilar receptacles of equal impressions, similar effects could 

 never be produced ; a thing incompatible with the divine perfections, 

 and with the innumerable testimonies of varieties occurring in the 

 whole of nature. 



When these authors therefore admit the perception of sounds, and 

 yet deny the organ of hearing, they appear to me to stand in the same 

 predicament as if they had said that insects indeed hear, but yet they 

 do not hear truly ; than which nothing could be conceived or expressed 

 more absurd : and the same may be said of fishes and many other 

 animals, the sense of hearing in which has been altogether denied by 

 Pliny, Ardern, Linnaeus, and many others, while Nollet has expressed 

 himself doubtfully ; but Allein, Boyle, Bradley, Pejer, Uffenbach, and 

 Bergman, give strong proofs and arguments against it, although the 

 organs are accurately described by Camper, and are often visible exter- 

 nally, though not always. A very difficult question occurs here, namely, 

 whether the situation of the ears thus denied to insects can be filled 

 by the antennae, which though a conjecture new and hitherto unheard 

 of, seems to me very probable. The form itself and hollow structure 

 of the antennae, accurately observed, differs indeed very much from the 

 inner structure of the ears of other animals, but seems to approach as 

 near as possible to the form of the semicircular canals,, which always 

 exist not only in the inmost recesses of the ear of quadrupeds and birds, 

 without any exception according to Perault, Senac, and other zooto- 

 mists ; but likewise in the obscure organs of amphibious animals and 

 of fishes, in which frequently there is not even the least trace of the 

 bones of the drum or of an external ear. Duvernay, Richter, and Geof- 

 froy bear testimony that they are to be found, with a very few excep- 

 tions, so constantly, that they seem as it were indispensable in the parts 

 belonging to the ear ; wherefore it is said by many, and particularly 

 Haller, not improperly to form the seat of hearing, or receptacle of the 

 impression of sounds. Nor in that comparison does any thing displease 

 me, unless that the antennae and the joints, for the purpose of exciting 

 motion, are placed where the bony semicircular canals are concealed 

 between the bones of the temples : which variety however cannot pre- 

 vent the nerves destined for the sense of hearing from being disposed 

 generally, as to its layers, equally in each kind of hollow, although the 



