1885.] Zoblogy. 187 
comparable to a segmental sense organ. As in the latter the 
cells on the free surface possess long hairs. These hairs like 
those of the segmental sense organs are concerned with the per- 
ception of wave-motions of the medium in which the animal lives. 
The hairs on the auditory cells are indeed concerned with the 
perception of much finer wave-motions—those of sound—than 
those on the cells of the segmental sense organs, and hence arises 
the early shutting off of this organ from the skin. The inner 
layer of cells of the auditory organ is exactly comparable to the 
inner layer of cells of a segmental sense organ 
In Teleostei, etc., the auditory organ beedmes entirely shut off 
from the skin, ut in Elasmobranchii the aperture of invagina- 
tion persists, and the organ is —— ma the surface through- 
out life, just as the segmental sense or 
ese facts, together with the fact that the auditory nerve is 
merely a dorsal sensory branch of a segmental nerve, seem to 
point to the conclusion that the auditory organ of vertebrates is 
fundamentally a specialized portion of the system of sense organs 
of the lateral line, specialized above the rest of the system by the 
acquirement of the more delicate function of the perception of 
waves of sound. 
In accordance with, and as a direct consequence of this func- 
tion of receiving waves of sound, the auditory organ has been 
early shut off from the external surface, and has developed ac- 
cessory structures in the shape of semicircular canals, etc. Thus 
its primitive simplicity has been lost. 
I hope shortly to give elsewhere a more detailed statement of 
the points touched upon in this paper.—Fokn Beard in Zoölog-' 
ischer Anzeiger, 1884. 
SOME PRELIMINARY NOTES ON THE ANATOMY OF FISHES.— 
. On the cutaneous Sense-organs.—Since the distinetion between 
endknospen on the one hand, and nervenhiigel, nervenletsten, ner- 
ae on the other, is generally recognized, it becomes desi-. 
their shape, the term neuromast with the adjectival form neuro- 
mastic. 
At the meeting of the British Association in Montreal, in Sep- 
tember, I pointed out that the catfish possesses neuromasts in 
sacs, recalling those of the sturgeon. They resemble these, in 
ct, more closely than do the similar structures of Amia an 
Lepidosteus, which I have recently studied. The neuromasts 
belonging to a group are connected by a canal lodged in the 
corium, which is lined and in places filled by an epithelium, con- 
tinuous with the epithelium of the .neuromasts. Such a canal 
