48 Part IIL.—Twenty-fourth Annual Report 
IIl.—OBSERVATIONS ON THE OTOLITHS OF SOME 
TELEOSTEAN FISHES. 
By Tuomas Scort, LL.D., F.L.S., Mem. Soc. Zool. de France. 
(Puatzs I.-V.) 
ConrTENTs. 
PAGE. 
(1) Preliminary Remarks, ; ‘ 3 48 
(2) List of Fishes whose Otoliths are described, . 52 
(3) Systematic description of the Otoliths, . 53 
(4) Literature bearing on the Otoliths of Fishes, . 80 
I.— PRELIMINARY REMARKS. 
Rather more than twenty-five years ago a portion of my leisure was 
devoted to a study of the post-tertiary and surface geology of the Clyde 
Valley. Consequently, the rich fossiliferous beds that were exposed 
about that time in connection with the excavations for the James Watt 
Wet Dock at Greenock were of special interest to me as well as to all 
engaged in this study. It was about that time and in connection with 
these researches that my attention was first directed to those curious 
bodies known as the otoliths, or earstones of fishes. 
These studies had made me acquainted with the late Dr. David 
Robertson, of Glasgow, and subsequently of Millport, whose name is so 
intimately associated with the Marine Biological Station at the latter 
place. This gentleman, who already possessed large collections of 
natural history objects of various kinds, had among them an extensive 
series of the otoliths of recent and known fishes, and these collections I 
had the frequent privilege of inspecting. 
If I remember rightly, one of the reasons which induced Dr. Robertson 
to make this collection of otoliths was that such objects were expected to 
occur, or had already been noticed, in the fossiliferous clays then under 
examination, and that, therefore, a familiarity with the recent forms might 
help in identifying the kinds of fishes such fossil otoliths might belong to. 
With Dr. Robertson’s assistance, always freely given to those engaged 
in natural history pursuits, I soon became interested in these things. 
Later on, when carrying out the work assigned to me by the Fishery Board 
for Scotland, the food of fishes engaged my attention from time to time, 
and in order to obtain the information desired it was necessary to 
examine the stomachs of many of the fishes captured. As this 
examination proceeded it became manifest that small fishes were often 
captured by the larger specimens for food, as their remains sometimes 
formed a considerable proportion of the contents of the stomachs examined. 
Frequently, however, the otoliths or earstones were the only parts that 
remained, or that were least affected by the action of the digestive fluid; 
it was therefore obvious that a familiarity with the earstones of fishes 
