The literature is open to the general criticism that the strange and exceptional is noted, while by far the more important, common, and usual occurrence rarely appears in print; and thus queer stories of dogs and cats, horses, mules, birds, insects, and even men, who are able to point unerringly north, no matter how blindfolded or manipulated, come to predominate. Still, as the methods of animals have come to be studied with scientific
Flight of six pigeons, open cage.
accuracy, these notions have been compelled to flit from one form to another in most lively fashion.
Migratory birds, most careful study has proved, learn their route from "zone to zone," and follow it solely by means of vision. "This," Mr. Wallace says, "is now well ascertained." The work of Sir John Lubbock, of Forel, and the perfectly conclusive experiments of Mr. and Mrs. Peckham, leave no resting place for
- For a running discussion of the subject, refer to Science, voL xx, pp. 207, 248, 291, 318, 358.
- Rudski. Ueber ein angeborenes Gefühl der Kardinalrichtung des Horizonts. Biologisches Centralblatt, vol. xi, p. 63.
- Proceedings of the Natural History Society of Wisconsin, 1887, pp. 113 ff.