Chap. VIII. Proportio?i of the Sexes. 249 



FISH. 



With Fish the proportional numbers of the sexes can be ascertained 

 only by catching them in the adult or nearly adult state ; and there 

 are many difficulties in arriving at any just conclusion." 9 Infertile 

 females might readily be mistaken for males, as Dr. Giinther haa 

 remarked to me in regard to trout. With some species the males are 

 believed to die soon after fertilising the ova. With many species the 

 males are of much smaller size than the females, so that a large 

 number of males would escape from the same net by which the females 

 were caught. M. Carbonnier, 70 who has especially attended to the 

 natural history of the pike (Etox lucius), states that many males, owing 

 to their small size, are devoured by the larger females ■ and he believes 

 that the males of almost all fish are exposed from this same cause to 

 greater danger than the females. Nevertheless, in the few cases in 

 which the proportional numbers have been actually observed, the 

 males appear to be largely in excess. Thus Mr. R. Buist, the superin- 

 tendent of the Stormontfield experiments, says that in 1865, out of 70 

 salmon first landed for the purpose of obtaining the ova, upwards of 60 

 were males. In 1867 he again " calls attention to the vast disproportion 

 ■* of the males to the females. We had at the outset at least ten males 

 " to one female." Afterwards females sufficient for obtaining ova were 

 procured. He adds, " from the great proportion of the males, they are 

 "constantly fighting and tearing each other on the spawning-beds." 71 

 This disproportion, no doubt, can be accounted for in part, but whether 

 wholly is doubtful, by the males ascending the rivers before the 

 females. Mr. F. Buckland remarks iu regard to trout, that " it is a 

 " curious fact that the males preponderate very largely in number over 

 " the females. It invariably happens that when the fir&t rush of fish is 

 " made to the net, there will be at least seven or eight males to one 

 "female found captive. I cannot quite account for this; either the 

 '• males ore more numerous than the females, or the latter seek safety 

 " by concealment rather than flight.'' He then adds, that by carefully 

 searching the banks sufficient females for obtaining ova can bj found. 78 

 Mr. H. Lee informs me that out of 212 trout, taken for this purpose in 

 Lord Portsmouth's park, 150 were males and 62 females. 



The maies of the Cyprinidaa likewise seem to be in excess ; but 

 several members of this Family, viz., the carp, tench, br^am and 

 minnow, appear regularly to follow the practice, rare in the animal 

 kingdom, of polyandry ; for the female whiht spawning is always 

 attended by two males, one on each side, and in the case of the bream 

 by three or four males. This fact is so well known, that it is always 

 recommended to stock a pond with two male tenches to one female, or 

 at least with three males to two females. With the minnow, an 

 excellent observer states, that on the spawuing-beds the males are teu 

 times as numerous as the females; when a (emtio comes amongst the 



69 Leuckart quotes Bloch (Wag- 18, 1869, p. 309. 



ner, ' Handworterbuch der Phys.' 71 'The Stormontfield Piscicuh 



B. iv. 1853, s. 775), that with fish tural Experiments,' 1866, p. 23. 



there are twice as many males as The 'Field' newspaper, June 29th, 



females. 1867. 



70 Quoted in the 'Farmer,' March n ' Land and Water.' 1868. p. 4 J 



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