SALMONlD^E. 105 



of winged insects acceptable to these fish ; as a rule if the water is clear and low, 

 and wind is absent, small ones are most suitable : if clearing after a flood, or full 

 bat not discoloured the fly-fisher has more chance of sport, as well as if late in the 

 season when few flies are born. When the water is opaque a worm or spinning 

 bait may be tried with success. In small streams real flies and grasshoppers may 

 be used as bait for hooks on a short line, which is bobbed on to the surface of 

 the stream from over a bush. If once pricked by the hook it is generally but not 

 invariably shy : while it is disturbed by flies clumsily thrown or splashing into 

 the water. Frosty weather checks trout moving, and while snow water, or that 

 derived from the melting of snow, is running into a stream it is almost useless 

 attempting to use the rod. 



Baits. — Worms as brandling, gilt-tail meadow worm, tag worm and red 

 worm — -for a large one a well scoured dew worm. A minnow or any small silvery 

 fish, a loach, or a bull-head with its fins removed. 



Breeding. — The number of eggs produced by each female trout has been 

 roughly estimated at 800 for every pound's weight of the fish, which computation 

 has been observed at the Howietown breeding ponds to be fairly accurate. But 

 the size of the parent exercises a considerable influence on that of the eggs, thus 

 in Sir J. Gibson-Maitland's fish house we found the following average numbers 

 to be present along each line of grilles. Brook-trout 29 to 30 eggs ; Loch Leven 

 trout, the parents of which were hatched in 1875, 27 or 28, or from those hatched 

 in 1877, 32 eggs ; and the American charr 36 to 38.* The colour of the eggs are 

 as various as observed in the salmon, and I have seen some orange, others straw- 

 coloured, from two fish taken together out of the same stock pond. 



The period at which these fish breed varies in different rivers and districts, 

 extending from September until February and even March. Mr. Harvie-Brown 

 at Loch Gorm, in Sunderland, which is greatly fed by snow water from the Bact 

 of Beumore, has taken trout heavy with spawn in June and July.f It has been 

 questioned whether these fish are annual or biennial breeders, and Dr. J. Davy 

 came to the conclusion, after examining a large number captured in open streams, 

 that only half spawned annually. At Howietown, on the contrary, it would seem 

 to be the rule that an annual spawning occurs, and though such a question is 

 difficult to settle an instance in point has been observed. A marked example of 

 Loch Leven trout was spawned at Sir J. Gibson-Maitland's on November 27th, 

 1874, and again on November 25th, 1875. At Howietown, where about one 

 million of gallons of water flow through the ponds every twenty-four hours, the 

 fish develop spawn and milt as regularly as in their native habitat, some even pass 

 up the aerating channels forming redds there. But in ponds destitute of streams, 

 certainly no young are produced, either spawn not being developed, remaining 

 unfertilized, or else from being deposited in an unsuitable place (see page 91). It 

 has been generally considered that when the ova of these fish have arrived at a 

 certain stage the female has no power to retain them but they must be extruded, 

 a conclusion Sir J. Gibson- Maitland has found reason to doubt, as it seemed to 

 him that a certain amount of pressure is necessary to assist in the discharge of the 

 eggs, and which is normally effected by pressing against the gravel forming the 

 redds. Acting on this opinion he has found it possible to retard the extrusion of 

 of the eggs for as much as a fortnight or even three weeks, by placing the fish in a 

 wooden box through which a current of water flows. 



A trout's redd or nest is a mound of gravel which would fill one or even two 

 wheelbarrows, and probably by causing a shallow, assists in aerating the water. 

 The eggs themselves lie loose among the gravel at from one to two feet below the 

 surface. Eggs when shed are elastic, but soft and sink in water : when artificially 

 propagated the milt of the male is generally added to the eggs in the pan prior to 

 the addition of water, subsequently water is added and the mass is gently stirred 



* The rough calculation of eggs of Salmonidae is that Salmo salar gives 25,000 to the gallon, 

 8. levenensis 30,000, 8- Jario 40,000, 8. fontinalis 80,000. 



f Mr. l Jgilby (co. Tyrone) observes that there is not a montb in the year, during which it is 

 legal to fish, in which trout do not spawn. 



