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 surveys in 1850 brought considerable collections of birds from the western United States, that we learned that many birds of the more arid west were decidedly different from their representatives in the more humid east. In most instances of this kind we at first had only two forms, an eastern and a western, but subsequent exploration added to the material available for study, and it was discovered that every region possessing marked physiographic and climatic characters had races peculiar to itself, and for the first time the laws of geographic variation, or of evolution by environment, became evident. This is one of ornithology's most valuable contributions to philosophic natural history; an epoch-making discovery the practical application of which, in the vain attempt to definitely name the indefinite, has led us into our present difficulties. Thus it has happened that of the 1,068 birds included in the 1895 edition of the A. O. U. 'Check-List,' 300 are ranked as subspecies, or, in other words, a subspecies for every two and a half species. But the end is not yet. Since 1895, over seventy so-called 'new' forms have been described and with each fresh revision of a variable group the 'splitting' becomes finer and we are afflicted with added names the application of which is doubtful. As a matter of fact, specimens are no longer separated from specimens, but series of specimens from series of specimens, and herein lies the evil of splitting as it is at present practiced.

We have long passed the stage in our study of the climatic variations of North American birds, when we should expect to discover a subspecies so marked that its characters would be convincing in a single specimen. In fact, large series are usually necessary to make apparent the differences on which it is proposed to separate one bird from another. Placed side by side, it becomes evident that one row of birds, as a row, is more or less unlike the other row, and the cumulative differences of perhaps thirty birds are, in describing such forms, ascribed to one, whereas, to a degree, in resolving the series of thirty birds into its component individuals, the value of the characters attributed to the new form are in effect divided by thirty, that is, theoretically, are evenly distributed among the thirty birds of the series. The probabilities are, of course, against so even a division of differences, but the series will, undoubtedly, contain birds in which the characters attributed to the form are almost wholly wanting. A case in point is furnished by an ambitious splitter, who admits that a series of thirty-six specimens "barely suggested" differences, on which, however, with the assistance of eleven additional specimens, he proposes to found a new subspecies! Now, while we cannot over-estimate the importance of determining with the utmost exactness the geographic variations of birds in further elucidating the laws of evolution by environment, we maintain that the recognition by name of such minute and inconstant differences as we have indicated is a perversion of the uses of zoological nomenclature and a menace to the best interests of ornithology.

The layman, whether or not he is inclined to sneer at the closet naturalist, bows to his authority and accepts without question his ruling, whether it be a new name or a new nomenclature. But if we do not mistake the signs the lay ornithologist has become so confused in a vain effort to keep pace with the innovations of the professional, that he is on the border of revolt against what, in the main, he esteems to be a needless juggling with names.

Fortunately, there is a court to which we may appeal in this difficulty. The American Ornithologists' Union, appreciating the need of revision of the work of too enthusiastic systematists, has a standing committee, whose duty it is to pass on the species and subspecies of North American birds, which have been described since its last meeting, with the laudable object of excluding those which seem unworthy of recognition by name. We appeal, then, to this committee to protect us from the undue development of a practice winch is bringing systematic ornithology and some systematic ornithologists into disrepute and. by rendering accurate identification impossible, proving a needless source of discouragement to students of birds.