110 C:ipt. G. E. II. Barrett-IIainilton on the 



nected with the iDuscuhw work aiul to what extent with tlie 

 growth of tlie genitalia ?" (p. 2). 



Such were some of the questions to tlie investigation of 

 which the scicniific officials of the Scotch Fishery Board 

 devoted themselves, lirieflj stated their conclusions, so far 

 as fhey relate to my own paj)er, are : — 



" That the genitalia of fish coming from the sea develop 

 steadily from April on to the spawning-time, and that the 

 genitalia of salmon in the earlier summer months develop 

 more rapidly than tliose of grilse. 



" That the projwrtion ot the weight of genitalia to the 

 weight of the fish is constant tor all sizes of salmon " (p. 2), 



Dr. Noel Paton and Dr. James C. Dunlop agree in con- 

 firming the conclusions arrived at by Mr. Archer* in a 

 previous report, "that fish continue to feed in the sea at least 

 till the end of August. The marked diminution in the amount 

 of muscle in fish reaching the estuaiies in October and No- 

 vember would seem to show that the sup[)ly of food is insuffi- 

 cient to yield the materinl necessary Ibr the rapidly growing 

 genital glands, and that therefore the solids of the muscle 

 have to be drawn upon, or, at least, that accumulation of 

 material in the muscles is prevented. The steady increase in 

 weight per fish of standard length throughout the season 

 seems to indicate that they continue to feed even after August 

 and September, though, as will be shown later (p. 8(i), the 

 fiesh contains about 5 per cent, more water in October and 

 November than in July and August, while the increase of 

 weight is only 3-7 per cent. 



" 2nd. The fall in the amount of muscle from the early to 

 the late part of the season in fish in the upper reaches supports 

 the conclusions arrived at by ]\Ieischer Ruesch, and by 

 Drs. Gulland and Gillespie, that the salmon does not teed in 

 fresh water " (pp. 74-75) . 



If, then, as has already been shown, the salmon, leaving its 

 niarine feeding-ground, ascends the river and remains until 

 the spawning-time, oi'ten for several months, without any 

 supply of nourishment from without, during this period it 

 must subsist upon the store of material in its body brought 

 from the sea. It is to a study of " the j)rogress of the changes 

 which go on in the fish during its ])rol()nged fast" and an 

 attempt to explain " how the material for the growth of the 

 genitalia and tor the muscular energy required in the ascent 

 ot the stieam is obtained " (p. 79) that a great portion of the 



* See 'Annual Reports vf (he Fi^lierv Buarcl for Scotland,' jiart ii., 

 189;-,. 



