ON MALFORMED TROUT FROM SCOTTISH WATERS 93 



scissors cut off a large portion of the fin, and trimmed 

 it into the peculiar and abnormal shape which it now 

 presents. 



In the following year (1872) Mr. James Thomson, F.G.S., 

 published a paper l in which he minutely described the posi- 

 tion of the lake, both geographically and geologically, giving 

 also two woodcut figures of the trout themselves, in one of 

 which the tail-fin appears simply rounded, in the other 

 rounded-acuminate, as it shows a little point projecting from 

 the middle posteriorly. In this paper Mr. Thomson states 

 that he had not found any of the fins save the caudal affected 

 by this peculiar abnormality, and gives to the fish the dis- 

 tinct name of Salmo Islayensis. 



About the same time I published a brief anatomical 

 description, with figures, of the "Tailless Trout of Islay,"- 

 taken from two specimens given to me by Professor (now 

 Sir William) Turner and Mr. Peach. Here, besides giving 

 an account of the essential nature of the malformation of the 

 caudal fin, I demonstrated that a similar condition was also 

 present in the anal and pectoral fins of the larger specimen, 

 the dorsal and caudal remaining alone unaffected. 



On the occasion of the " Tailless Trout " of Islay being first 

 exhibited to the British Association by Mr. C. W. Peach, the 

 late Dr. Grierson of Thornhill in Dumfriesshire mentioned 

 that he had heard of similar " docked " trout having been 

 taken near Wanlockhead, but I have never seen any speci- 

 mens from that locality, nor have I heard of any such having 

 been described or figured. It was not until the year [882 

 that Mr. Harvie-Brown afforded me ocular proof of the 

 occurrence of this malformation in trout from a locality in 

 Scotland far distant from Islay, by presenting to the Museum 

 of Science and Art two specimens from Loch Enoch in 

 Kirkcudbrightshire, which he had obtained from Mr. Adam 

 Skirving of Croys. Of these I published a description in 

 the same year, 8 in which I showed that not only was the 

 malformation of the caudal fin of precisely the same nature 

 as in the Loch-na-Maorachan fish, but that here also the anal 



1 •■ Sciei ip," Api il 



2 "Journ. Anat. & Physi< I. vi. 1872, pp. 111-416, pi xix. 



:: " Proc. Roy. Phys. Soc. Edinburgh," vol. vii. 1882, pp. 221-223. 



