IOWA ACADEMY OF SCIENCES. 101 



tically the same thing, to keep the females from sharing in the increased 

 size of the males. 



The advantage referred to arises from the manner in wiiicii the females 

 are handled by the males upon the landing of the former, which is descriljed 

 as follows by Elliott: 



"The little covvs have a rough-and-tumble time of it when they begin to 

 arrive; for no sooner is the i)i-etty animal fairly established on the station of 

 bull number one, when bull number two, seeing bull number one off his 

 guard, reaches out with his long, strong neck and picks the unhappy but 

 passive creature up by the scruff of hers, just as a cat does a kitten, and 

 deposits her on his seraglio ground; then bulls numbers three, four, etc., in 

 the vicinity, seeing this high-handed operation, all assail one another, and 

 especially bull number two, and have a tremendous tight, perhaps for half a 

 minute or so, and during this commotion the cow genei-allj- is moved or 

 moves farther back from the water, two or three stations more, where, 

 when all gets quiet, she usually remains in peace." 



Allen also quotes Captain Bryant as follows: "Frequently a struggle 

 ensues between the two males for the possession of the same female, and, 

 both seizing her at once, pull her in two or terribly lacerate her with their 

 teeth." 



It is evident that the more easily and quickly the females can be moved 

 the better for them, as they are thus more likely to avoid being lacerated by 

 the males, either in being stolen from one by another, or in being fought 

 over as described in the last quotation. If this is true, the lighter females 

 would be less likely to be injui-ed by the savage males, and hence the heavier 

 ones would be weeded out by a natural selection, which by its constant 

 action would go far toward accounting for the great sexual disparity exhib- 

 ited by these animals. 



The remaining fact demanding explanation is the wonderful ability of the 

 male sea lions to endui-e long-protracted fasts. On this point Mr. Elliott 

 says that they '■ abstain entirelj' from food of any kind or water for thi'ee 

 months at least, and a few of them stay four months before going into the 

 water for the tirst time since hauling up in May." 



"This alone is remarkable enough, but it is simply wonderful when we 

 associate the condition with the increasing activity, restlessness, and duty 

 devolving upon the bulls as heads and fathers of large families. They do 

 not stagnate, like bears in caves." 



It seems highly probable that this astonishing ability to endure protracted 

 fasts is one of the results of the ultra polygamy practiced by these animals. 

 A marked intensification of desire seems to be one of the immediate con- 

 committants of polygamy among animals. A writer in a recent number of 

 th^ *Xnttiralist, says, in speaking of monogamous birds adopting a polyga- 

 mous habit: "We may infer, therefore, that sexual power and high sexual 

 characters go hand in hand, and that in proportion to the advance toward 

 organic perfection virility increases." 



The virility of the sea lion is probably more excessively developed than 

 that of any other mammal. The sexual organization is of the most highly 



* Anierioan Naturalist, Novemljcr, 1890. p. 1030. 



