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Show 582 MR. F. DAY ON BACES AND [Dec. 2, trace of an indistinct line of spots along its base. The other fins more or less lead-coloured with light edges. On October 4th I received from Howietoun a grilse 13 inches long, which had either jumped out of the pond (no. 7) or been dragged out by vermin, and was dead when found. It was a female, with the eggs 0*2 of an inch in diameter, or double the size of those from the fish of August 28th. Colours-two irregular rows of black spots existed along the base of the dorsal fin. A n injury close to the pectoral fin was present, as if the fish had been bitten by rats or injured by sea-gulls. O n November 7th a grilse \\ lb. weight was found lying almost dead by the side of the pond ; some (over 100) apparently ripe eggs were obtained from it, and the milt of a Lochleven Trout used to fertilize them. Prior to giving an account of how we found the young Salmo salar going on, I should mention that pond no. 7, in which they were located, is lined with wood at the sides and bottom, is 100 feet long by 15 feet wide, 8 feet deep in the middle and 6£ at either end, inside measure, while the supply received is from half to one million gallons of water a day. Owing to the grilse constantly jumping at the sides, wire-netting to one foot in height was fixed around the edge of the upper half of the pond. About the middle of October fungus appeared among the fish, apparently due to injuries, as owing to the nature of the pond no suitable locality for depositing ova is present, and it seemed as if the females were constantly jumping in order to overcome obstructions1, and find a way to where they could construct their beds. Owing to this injuries are occasioned, and these seem sure to eventuate in fungus. The Limnaa thrive in this as well as in the other pond, but young Salmon do not seem to eat them, whereas Trout or Char at once devour them. November 14th, pond no. 7 had the water let off2, as it required cleaning out and re-charring this year, the fish being in the mean time transferred to the brook-trout pond, which has just been re-done up, while its former inhabitants have been turned into the brook as being too old to be worth keeping ; sixty-eight fish were transferred, the majority being males. These fish showed all the gradations of colouring, from the golden-banded parr to the silvery smolt wherein parr-bands were visible in certain lights, up to grilse which possessed milt or were distended with ova. Such examples as were in the parr-livery were males, but silvery smolts with parr-bands and also grilse had milt. Unfortunately the gravid females were to a great extent affected by fungus consequent on injuries ; still one gave about two dozen eggs, which were milted from one of the males. Another week or even fortnight would have to elapse before it will be practicable to obtain eggs. Three which were too much injured to live, 1 This phenomenon is not restricted to migratory forms, as species of many genera of the Carp family may be observed in Southern India or Sind springing in the same way at the impassable weirs which cross some of the rivers' up which they ascend to breed. F 2 In the m u d were many prides, Petromyzon branchialis. |