1891.] Polygamy Among the Pinnipedia. 107 
amount of social immorality found among the crowded tenements 
of our large cities. Constant opportunity offers the most power- 
ful temptation to gratify desire, and this is doubtless as true among 
Pinnipedia as among men. The result of this is a departure from 
strict monogamy in the direction of promiscuity. The harbor 
seal (Phoca vitulina) illustrates this stage in the process. So far 
as I can ascertain, this species is simply promiscuous in sexual 
affairs, but does not attain to polygamy in the sense used here. 
The sexual disparity is slight, the males being somewhat heavier, 
and but little, if any, longer than the females, 
3d, The departure from monogamy in the direction of pro- 
miscuity results in constant rivalry on the part of the males to 
possess the most attractive, or the greatest number, of the females. 
Rivalry begets warfare, the world over. This purely individual 
and personal rivalry among the male Pinnipedia results in indi- 
vidual combats, in which courage, ferocity, and size are the con- 
trolling factors. We thus have instituted the most rigorous 
kind of sexual selection, by means of which the above desirable 
qualities are secured, propagated, and intensified on the part of the 
males. The females, on the contrary, seem to be practically 
passive. The writer has been unable to find any evidence that the 
female Pinnipedia exercise any choice in the matter of accepting 
or rejecting individual successful males. The sexual selection 
_ thus instituted is true sexual selection as defined by Darwin 
as follows: “This [sexual selection] depends on the advantage 
which certain individuals have over other individuals of the same 
sex or species, in exclusive relation to reproduction.” ™ It differs, 
however, from a vast majority of instances of sexual selection in 
apparent absence of choice on the part of the female. 
This stage in the development of polygamy is illustrated by 
the hooded seal (Cystophora cristata), which appears to be pro- 
miscuous in sexual matters, and in which the males fight fiercely 
for the possession of the females. The divergence in sex has 
become considerable, as already indicated, the males being more 
than twice as heavy as the females. 
_ §This word, although questionable, is the only one known to the writer by which 
the meaning, indiscriminate intercourse, can be tersely exp 
1 The Descent of Man, p. 248. The italics are mine. , 
