[92]

(92

Charles Darwin ─ The Descent of Man

 

This fact seem is so well established that in stocking a pond with tenches, it is always advisable advised always to place males in it two males to in the proportion of two males to one female, or at least of 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 [came] amongst the males, "she was immediately pressed closely by a male on each side; & when they have been in that situation for a time, are superseded by other two males."* (S)

Insects

In this class, the Lepidoptera alone afford any means of judging of the proportional numbers of the sexes; for they have been largely collected with special care by many good observers & have been largely bred from the egg or caterpillar state. I had hoped that some breeders of silk-worms moths might have kept an exact record, but after writing to France &