of the Fishery Board for Scotland. 



103 



In Scotland we have the valuable observations from the Tweed of 

 Tosh and Grey, reported by my predecessor in the Thirteenth and 

 Fourteenth Annual Reports of the Fishery Board for Scotland, Part II. 

 Tnthis instance 6018 fish were examined not merely by external obser- 

 vation, but by the actual examination of the genitalia. 4567 were 

 females and 1451 were males, a proportion of 100 males to 314 females. 

 When these results are combined with 4654 fish, the sex of which was 

 estimated by external observation, the following monthly results from 

 February to September (the open season) of the combined 10,672 fish 

 are obtained : — 



In February to 100 males there were 251 females. 

 „ March „ „ „ 349 „ 



„ April „ „ „ 392 „ 



„ May „ „ „ 320 „ 



„ June „ „ „ 349 „ 



„ July „ „ „ 312 „ 



„ August „ „ „ 276 „ 



„ September „ „ „ 288 „ 



Tiie discrepancy, which decreases with the advance of the season, leads 

 to the inference stated by the writers in question, that when the 

 spawning season has come round an approximate balance of sexes may 

 exist, as has been indicated by Meischer and by Hoek, but it is not 

 brought out by the returns for Norway. 



In the Annual Reports I receive from District Fishery Boards it 

 is always noticeable that the statements made from certain districts 

 differ essentially from those of other districts. While it is no doubt 

 true that the answers to the queries respecting the proportion of the 

 sexes are almost necessarily made in many cases from rather rough 

 estimates at uncertain times, it is nevertheless noticeable that such 

 reports are consistent from year to year and are borne out when 

 observation is made of the sexes of salmon netted after the close of the 

 season for the procuring of ova with which to stock hatcheries. Reports 

 from Caithness, Sutherland, and Ross generally go to show that in 

 these counties males predominate. Four to one is the proportion of 

 males to females reported from the Kyle of Sutherland. In the 

 Conon, the result of ova fishing at the spawning season for ten 

 consecutive years goes to show that there are two males to one 

 female. Thurso ova fishing at Brawl gives a similar result, and even 

 throughout the angling season in the County of Sutherland the report is 

 that " all the bailiffs estimate that males predominate." In the Spey 

 the sexes are reported as well balanced, while in the neighbouring River 

 Deveron " fish killed in the river by net and coble would be five females 

 to one male." In the southern counties of Scotland reports go to show 

 that females are most numerous, and therefore it is sufficiently clear 

 that distinctly opposite conditions are reported. 



It seems to me practically certain that a single female fish is attended 

 at the spawning season by a single male fish from before the making of 

 the redd till all the ova of the female are shed. It does not seem to me 

 equally certain that by that time the male fish is spent, and we are not, 

 I think, in possession of any facts to show either that a male after 

 attending a female through the deposition of her ova is found to be a 

 kelt ; or, on the other hand, that a male attends more than one female 

 during a spawning season. Noel Paton * states that in his opinion there 

 is little doubt that " as a rule male fish are ripe in the beginning of 

 " October, and that from that time onward they are capable of 



* " October salmon in the sea," Proc. Roy. Soc. Edinburgh, xxiv., Part v., 

 p. 486. 



