In connection with the scandalous conduct of a lady pigeon I shall presently speak of comparative psychology in the world of animals. The capacity of animals for emotion and sentiment is naturally the first psychic phenomenon presenting itself to the observer. Their manner of expressing the sensations received from the exterior world, and the impulses resulting from those sensations constitute what may without derision be called the moral life of animals, leading, just as it does in the case of man, to the best adjustment possible between the individual organism and surrounding conditions. Many good people will doubtless be distressed by the idea that morality, in which they take such pride, though not always preaching it by example, instead of falling from heaven in the form of indisputable commands, has its roots far down in the animate hierarchy. If they were willing to reflect, they would be able to understand that undeniable analogies of organism involve a corresponding analogy of function. Nothing further is necessary to show the high significance of a study of comparative sentimentality and the morality illustrating it, determined by the organism that the great mass of living creatures have in common. The amusing side of the thing is that the majority of those who will cry out against this statement will in the same breath speak of the "intelligence" of animals, and will quote some story about a dog or cat or elephant, without suspecting that their very manner of presenting the problem solves the question of its principle, and leaves them with the sole resource of rebelling against the consequences of that principle. But it is not my intention to speak, as the reader may be thinking, of Montargis' dog, or any other animal known to history, for the astonishing proofs of sagacity he may have given. As I mean to relate a very simple but authentic story of brotherly love between a bullfinch and a maker of wooden shoes, my subject is more particularly the exchange of sentiments between two species of animal, a phenomenon in which the kinship of souls is very clearly demonstrated. It is common enough for man to give affection to the animals that surround him, an affection generally proportioned to the service he expects of them. Disinterestedness is rarely coupled with power.