THE ORGAN AND SENSE OF TASTE IN FISHES. 
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JSfervmhugel ), though these latter occur in the skin of fishes in a great variety of 
forms, often resembling the terminal buds very closely. The innervation and 
functions of the two systems of organs are, however, wholly different, and they really 
have nothing to do with each other. I shall illustrate more fully in a later section 
of this paper the structure of the terminal buds and the details of their innervation. 
I here call attention merely to the important fact that both in structure and in nerve 
supply they resemble most closely the taste buds of the mouth. From this one 
naturally infers for them a gustatory function. Since, however, inferences are not 
in order when facts are available, I have undertaken to determine experimentally 
the function of these cutaneous sense organs of the communis system. 
The experiments which 1 have made are of an exceedingly simple nature, the 
attempt being to put the fish while under observation in as nearly normal conditions 
as possible and to utilize the ordinary feeding and other instinctive reactions so far 
as possible in the accumulation of the data. These, are the methods of the old-time 
observational natural history, it is true, as contrasted with the methods of precision 
of the modern physiological laboratory. They have, however, proved sufficient for 
their purpose, which was merely to determine the class of stimuli to which the 
terminal buds are sensitive, or the sensational modality which they serve, rather 
than to contribute to the chemical physiology of taste in general. 
The chief obstacle to experiments of this sort, and one which many observers 
seem to have made no serious efforts to overcome, is the natural timidity or shyness 
of wild creatures when kept in the confined and unnatural quarters necessary for 
close observation. The role played by fear in animal behavior has been vividly 
brought to our notice by Whitman (’99), and, like this observer, I find that young 
animals which have been reared in captivity are much more approachable and 
tractable under experimental conditions than adults which have been reared in their 
natural freedom. In fact, with several species I quite failed to get the adults to 
take food at, all in captivity, though they were under observation for long periods. 
REVIEW OF LITERATURE. 
Surprisingly little attention has been paid to the physiology of taste in fishes, 
and this literature is very scanty. On the other hand, the anatomical investigation 
of these sense organs has been extensively followed for nearly a century, though 
often in a blind and profitless way. The history of opinion upon the significance of 
these sense organs has been quite fully given by Merkel (’SO) in his great mono- 
graph published in 1880, and the earlier phases of this history need not be again 
reviewed further than to mention a few salient features. 
In 1827 Weber observed the taste buds on the peculiar palatal organ of the carp 
and correctly interpreted their function, lie also figured the brain of the carp, 
illustrating the enormous vagal lobes from which these taste buds receive their inner- 
vation. Leydig discovered in 1851 the terminal buds of the outer skin of fishes and 
gave a detailed account of their structure, which subsequent research has shown to 
be in some respects inaccurate. In 1863 F. E. Schulze gave a more accurate descrip- 
tion of the “ beche'i formigen Organe ” of fishes, in which he distinguished the specific 
sensory cells from the supporting cells. He also correctly inferred their function to 
F. C. B. 1902—16 
