120 F. DAY: PERIODS OF MIGRATION. 



course, they would appear to be slow to again return to it ; thus 

 Mr. Willis Bund remarks that there used to be a good fishery just 

 above the place where the tunnel passes under the river Severn. In 

 consequence of the boring operations, chiefly the blasting, the fish 

 have left that part of the river, and the fishery is almost worthless ; 

 and although the blasting has now (October 1885) ceased for some 

 time, the fish do not return. In the McCloud River the blasting 

 operations of the Constructive Corps of the Central Pacific Railway 

 Company prevented the parent salmon ascending the river as usual 

 (Livingston-Stone: Bull. U.S. Fish. Comm., 1885). But the remarks 

 of Sir W. Jardine and others must not be overlooked, that temperature 

 in estuaries is occasionally, at least, a cause as to the side they select 

 when migrating, for they have been observed to select the sunny side 

 during the cold months, and the shady during the warmer portions 

 of the year. 



But the period arrives when these fish consider it necessary to 

 migrate from the tidal portions of a river and ascend into the fresh 

 waters, where, instead of going with the tide, they have to pass on 

 against the stream ; and fishermen, at least in the Wye, appear to 

 consider that it is a rule, excepting during a fresh, that these migra- 

 tions take place chiefly during the night-time — in fact, so strong on 

 this point is the opinion of some, that they do not hesitate to say that, 

 were night-fishing in this river to be put an end to, their occupa- 

 tion would be gone. It may be worthy of investigation, whether the 

 constant netting to which these fishes are subjected is not one cause 

 of their selecting to ascend during the night-time. 



The salmon in the sea having stored up fat, especially on and 

 around its pyloric appendages, and possibly, especially if in the 

 autumn, being in such a condition that within a definite period its 

 roe or milt must be deposited, commences its migrations towards its 

 inland breeding-ground. Buckland remarked that when examining 

 spring fresh-run fish, he found the amount of fat on the pylorics less 

 than what is present on one entering rivers for immediate breeding 

 purposes. His investigations seemed to indicate that the fat in both 

 instances might serve as nutriment to them while they resided in 

 fresh water • and the reason why the fish maturing its eggs has an 

 excess of fat over one not so engaged, is supposed to be due to the 

 great amount of nourishment which is required by the females while 

 the eggs are rapidly maturing. 



In November 1885, being with Sir J. Gibson-Maitland searching 

 for salmon eggs at the Teith, near Stirling, we took a female, 15 lbs. 

 weight, so injured by seals that it succumbed. It was a clean silvery 



Naturalist, 



