SEXUAL SELECTION 829 



preponderate very largely in number over the females. It 

 invariahly happens that -when the first 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 are more numerous than the females, or 

 the latter seek safety by concealment rather than flight." 

 He then adds, that by carefully searching the banks suffi- 

 cient females for obtaining ova can be found. " 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 males of the Cyprinidaa likewise seem to be in ex- 

 cess; but several members of this Family, viz., the carp, 

 tench, bream, and minnow, appear regularly to follow the 

 practice, rare in the animal kingdom, of polyandry; for 

 the female while 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 

 spawning-beds the males are ten times as numerous as 

 the females; when a female comes among the males, "she 

 is immediately pressed closely by a male on each side ; and 

 when they have been in that situation for a time, are super- 

 seded by two other males. ' ' " 



Insects. — In this great Class the Lepidoptera almost alone 

 afford means for judging of the proportional numbers of the 

 sexes; for they have been collected with special care by 

 many good observers, and have been largely bred from 

 the egg or caterpillar state. I had hoped that some breeders 

 of silk-moths might have kept an exact record, but after 

 writing to France and Italy, and consulting various treatises, 



" "Land and "Water," 1868, p. 41. 



" YarreU, "Hist. British Fishes," vol. i., 1826, p. 30'7; on the Cyprinus 

 carpio, p. 331; on the Tinea vulga/ris, p. 331; on the Abramis brama, p. 336. 

 See, for the minnow (Leudsms phoxmus), "Loudon's Mag. of Nat. Hist," vol. 

 v., 1832, p. 682. 



