ME. F. DAY ON THE LOCH-LEVEN TEOUT. 
75 
exist between 8. caecifer (as be termed this form) and 8. fario 
are very striking. The pectorals of 8. caecifer, when expanded, 
are pointed; in 8. fario they are rounded. The caudal fin in 
8. caecifer is lunated at the end; in 8. fario it is sinuous or 
even. 8. caecifer has never any red spots ; 8. fario is scarcely 
ever without them. The caudal rays are much longer in 8. cae- 
cifer than in 8. fario, in fish of equal length. In 8. caecifer the 
tail-fin is pointed at the upper and lower extremities ; in 8. fario 
they are rounded. The flesh of 8. caecifer is of a deep red, that 
of 8. fario is pinkish or often white. The csecal appendages in 
8. caecifer are from 60 to 80 in number; in 8. fario I have never 
found them to exceed 46.” He also observed that this fish does 
not appear to be peculiar to Loch Leven, as he had seen speci- 
mens that had been taken in some of the lakes of the county of 
Sutherland. 
Sir John Kicbardson, in the ‘Fauna Boreali-Americana,’ l. c., 
remarked that in “ external form, the proportional size of various 
parts of the head and gill-covers, the size of the scales and the 
dentition, agrees with 8. lemanus Three individuals of 
the Loch-Leven trout that were dissected had each 73 pyloric 
caeca, and in one of them 59 vertebras were counted.” Yarrell 
added nothing to the previous descriptions. Knox, ‘ Lone Glens 
of Scotland,’ 1854, observed of this trout of Loch Leven, that it 
“ is a beautiful silvery dark-spotted trout, imagined by some to 
be peculiar to the lake. This, however, is not likely, since trout 
quite resembling those of Leven are found in many northern 
lakes ” (p. 36). He concluded, after citing some of the opinions 
of others, that he was “ disposed to think that tw r o species of 
trout inhabit Loch Leven, independent of the common river 
trout ; namely, the trout which lives on entomostracse, and comes 
into season in December, January, and February ; and the trout, 
which, feeding on the buccinum, and on flies, worms, and all the 
common food of the common river trout, comes into season later 
in the spring” (p. 37). In the ‘Proceedings of the Linnean 
Society 5 (Dec. 19th, 1854), Dr. Knox remarked that at first he 
thought this a specific form, “although anatomical investigation 
has not hitherto confirmed it.” 
Dr. Gunther, l. c., gave a fuller description than the previous 
authors whom I have quoted, He observed of this fish that it 
has the “ body much less stout than in 8. fario .... In the 
male sex a mandibular hook has never been observed. Maxillary 
