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almost invariable to find three on each side. Out of 3700 fish examined, only 
about 9 had their organs of hearing deficient. In the case of 3, they only 
existed on one side, in a fourth they were cartilaginous instead of bony, &c. The 
otoliths of fish with cartilaginous skeletons were not solid, but aggregations of 
minute rhombic crystals of carbonate of lime. And in the sturgeon, which 
occupied a place between the bony and cartilaginous fishes, the otoliths were of 
an intermediate character also. The largest of the three otoliths was the only one 
valuable in a scientific point of view, and this varied in shape in every possible 
way. The groove on the under surface was no longer, the speaker considered, of 
any value as a specific character. 
Mr. Higgins concluded his address by referring to the extensive collection 
which he had brought down, containing a portion of the result of 1 7 years work 
at the subject, including the otoliths of nearly 600 species, and by recommending 
these little bodies to the attention of the comparative anatomist, as being the 
only portion of the skeleton which possessed a specific distinctive character. 
The President, in inviting discussion, remarked that the results of 
Mr. Higgins were a striking instance of the method of inductive science 
to which he had alluded in the earlier part of the evening. 
Mr. W. W. Stoddart said that no one would thank Mr. Higgins for 
his address, and for the exhibition of his specimens, with greater sincerity 
than he did himself. He considered Mr. Grove's recent text of 
6 continuity ' (at his Nottingham address) as the cause of the difference of 
opinion between them, and of the views formerly expressed, but now 
modified. While allowing that fish did not hear as air-breathing animals 
did, he still considered that the office of these otoliths, was, from their 
density, to increase the vibration caused by the sound. 
Mr. Higgins controverted this, and pointed out that all animals which 
really and truly heard, gained experience by hearing, but that this was not 
the case with fish, and he regarded this as the strongest proof that fish 
did not hear, but believed that they felt through their whole body the 
vibrations caused by the sound. 
Dr. Henry Fripp considered Mr. Higgins' generalisations very 
valuable — especially with regard to genera. It was of the greatest 
importance, physiologically, to obtain characteristics of any genus, species, or 
class, connected with a sense so highly important as that of hearing ; these 
otoliths might be of the greatest importance, even more so than the 
' ossicula auditus ' in this respect. Considering that the office of the semi- 
circular canals was to indicate the direction of sounds, he thought that the 
otoliths might materially assist this function. On the greater or less per- 
fection of the sense, both for obtaining prey, and for indicating the 
approach of danger, the life of the fish depended. The noises made by 
the fish in water were received by them as vibrations, and in a paper read 
