That the desire for sexual congress is inherently more avid, more intense, in the male than in the female is often called in question; and more especially so by those who imagine that they have a mission to carry on “social reforms” and to regulate the relations between the sexes of the human race. Such aims and ambitions are commonly those of the arrogantly ignorant. There are few people who possess a sufficiently wide knowledge of this theme, or of the factors which underlie it, to qualify them to become the mentors of their fellow-men in these matters. However much we may choose to seek refuge in sophistry, the fact remains that man is still an animal, and if the human race is to continue he must always remain so. A lurid light has just been shed on the fierceness of the sexual passion in the male by Mr. Julian Huxley, who relates some facts pregnant with meaning to all who have understanding, in regard to what obtains among birds. These facts are primarily concerned with the Mallard (_Anas boscas_). This bird is ostensibly monogamous, and, on the whole, seems to be a fairly considerate mate. The normal period of pairing having passed, and the duties of incubation having begun, the female ceases to harbour any further desire for sexual intimacy. Her whole energies are devoted to nursing her embryonic young into life. Not so the male. He is yet far from satiated; in him the sexual fever still burns fiercely, but somehow he seems never to make any attempt to provoke in his mate a like condition, as in the days before brooding began. On the other hand, he does not scruple to savagely pursue every other female who ventures abroad in his neighbourhood. So soon as a duck takes wing for a brief relaxation from the arduous work of brooding she is pursued by ten or a dozen already mated males, till at last she is obliged to descend on the water, and with her descend her pursuers, now to mob her without mercy. Commonly at least half of these infuriated males will eventually succeed in treading her; leaving their victim only after she has become completely exhausted or killed outright. This is no unusual occurrence. On the reservoirs at Tring, where every spring from one thousand to one thousand two hundred pairs congregate to breed, from seven per cent, to ten per cent, of females are annually killed in this way. It is just possible, however, that an error may have crept into these observations. One cannot help asking, may it not be possible that these pursuing males were actually unmated birds? The chief argument against this is the fact that there is no sort of attempt to “display” apparent with these birds, simply an overmastering, ravenous desire to satisfy the craving which possesses them.