Naturally among such kinds no one member is of more consideration than another. But among mammals such equality and harmony is rare. The instinct of one and all is to lord it over the others, with the result that one more powerful or domineering gets the mastery, to keep it thereafter as long as he can. The lower animals are, in this respect, very much like us; and in all kinds that are at all fierce-tempered the mastery of one over all, and of a few under him over the others, is most salutary; indeed, it is inconceivable that they should be able to exist together under any other system. On cattle-breeding establishments on the pampas, where it is usual to keep a large number of fierce-tempered dogs, I have observed these animals a great deal, and presume that they are very much like feral dogs and wolves in their habits. Their quarrels are incessant; but when a fight begins the head of the pack as a rule rushes to the spot, whereupon the fighters separate and march off in different directions, or else cast themselves down and deprecate their tyrant's wrath with abject gestures and whines. If the combatants are both strong and have worked themselves into a mad rage before their head puts in an appearance, it may go hard with him: they know him no longer, and all he can do is to join in the fray; then, if the fighters turn on him, he may be so injured that his power is gone, and the next best dog in the pack takes his place. The hottest contests are always between dogs that are well matched; neither will give place to the other, and so they fight it out; but from the foremost in strength and power down to the weakest there is a gradation of authority; each one knows just how far he can go, which companion he can bully when he is in a bad temper or wishes to assert himself, and to which he must humbly yield in his turn. In such a state the weakest one must always yield to all the others, and cast himself down, seeming to call himself a slave and worshipper of any other member of the pack that chooses to snarl at him, or command him to give up his bone with a good grace. This masterful or domineering temper, so common among social mammals, is the cause of the persecution of the sick and weakly. When an animal begins to ail he can no longer hold his own; he ceases to resent the occasional ill-natured attacks made on him; his non-combative condition is quickly discovered, and he at once drops down to a place below the lowest; it is common knowledge in the herd that he may be buffeted with impunity by all, even by those that have hitherto suffered buffets but have given none. But judging from my own observation, this persecution, is not, as a rule, severe, and is seldom fatal.