590 THE SENSES AND SENSORY ORGANS. 
without indicating that they are the terminal organs of the 
antennal nerve; and he, on other occasions [269], described 
what he regarded as auditory end organs in the antenne of 
insects. 
Anatomy can only guide us in seeking the function of a part 
when the structures are similar to those of the human body. 
As the so-called olfactory sete of Invertebrates are entirely 
unlike the olfactory rods of Man and Vertebrates generally, 
the structure of these end organs cannot guide us to their 
function. I only know one anatomical fact which in itself is 
a guide to the function of the antenna: the structure of the 
antennal ganglion, which is similar to that of the olfactory 
bulb of the Vertebrate; but this was unknown until it was 
discovered by Dietl [175] in 1876. The credit of having first 
established the olfactory function of the antennz must be 
accorded to Perris [265], as he was the first who made a 
systematic investigation of their function in living insects 
by carefully devised experiments. 
Lespés [266] ignored the researches of Perris, and returned 
to the view of Oken. Claparéde [267], in 1858, published a 
paper in controversion of Lespés’ views; and Graber [270], in 
1879, believed that he had discovered otolith-like organs in the 
antenne of flies, and returned to Oken’s view. P. Meyer in 
the same year published a short paper in the ‘ Zoodlogische 
Anzeiger,’ in which he correctly stated that Graber’s supposed 
otolith-like bodies have no real existence. 
The views of Perris have been completely confirmed by the 
repetition of various experiments, and may be said to have 
been accepted, although, owing to the apparent multiplicity of 
the forms which the nerve terminals exhibit, there are still 
many who think that the antenne may have an auditory as 
well as an olfactory function in some insects. 
Krapelin [278] has given so complete a history and criticism 
of the works of previous writers, that I shall content myself 
with the above short account of the history and bibliography 
of a controversy, of which the last-named author says: 
‘An extensive literature has grown in the course of years, 
