The history of domesticated animals is a continuous proof that some at least of the lower creatures are capable of learning, and how learning can be achieved without intelligence has never yet been explained, and is never likely to be. But Mr. Wallace points out that we have made a gratuitous assumption, unsupported by evidence, in supposing birds, for example, to build their nests by instinct rather than by following the example and instruction of their parents. Many things, he remarks, which we ourselves are said to do instinctively, such as putting out our hands to save ourselves from falling, are acquired habits, not instinctive actions, and in fact not possessed by infants. Mr. Darwin[31] tells us of a species of ant which behaves differently towards its slaves in England and in Switzerland respectively. In his memorable account of the busy bee, he shows that some species of bees are less clever at their work than others, and that the accuracy even of the most advanced cell-makers has been overrated. This is the more worthy to be noted, because the same persons who are extremely zealous to set forth reason as superior in kind to what they call instinct, are yet often eager to extol the effects of the lower faculty above those of the higher. An interesting account has recently been given of baboons in the neighbourhood of the Cape of Good Hope combining to pursue, and after a chase of two days and a night, successfully destroying a leopard which had invaded their haunts. Two tribes of baboons in the same locality, the occupants of separate rocky strongholds, are described as upon one occasion meeting in battle, the result being, that nearly a hundred were afterwards found dead or dying on the scene of action[32]. The shape of the creature, and the combination for warlike purposes, which carries with it such a tinge of humanity, can scarcely fail to affect the imagination. Yet these isolated instances must be far less telling than the comparison which Mr. Wallace has so ingeniously instituted between man as a builder and birds in the same capacity. The shelter of the savage is in many cases a less finished contrivance than the nest which the bird prepares for its young. The featherless biped, like the feathered one, takes the materials readiest to its digits. Generations upon generations follow one another without improvement or signs of inventive skill. Even in the days of enlightenment, and in nations which pride themselves most upon it, the human nest is repeatedly constructed without the smallest attention to comfort, health, or beauty. Men, whose fathers before them have built long rows of red-brick boxes to live in, build, by instinct if you will, for it can scarcely be by reason, more lengthening chains of red-brick boxes. There is no reason, indeed, for supposing that the bird consults any principle of beauty in the construction of its nest, but a principle of expedience some birds