The purely scientific side of ornithology (and of botany, too, it must be confessed) is as yet too much of a makeshift to be very captivating, even to those whose predilections are of an intellectual rather than of a sentimental sort. Its principles of classification are not yet very profoundly established, and by the highest authorities upon the subject are confessedly tentative. In counting the number of feathers in the wing, and in examining the anatomy of a bird's foot, for tests of relationship, we hardly penetrate deep enough into the real nature of a bird to feel any intense glow of enthusiasm. Swallows, warblers, and finches are temperamentally different; - a difference by no means accounted for by existing criteria of classification. And botany is not in advance of ornithology in this respect.