When the investigations of geologists show reason for believing in radical changes in the forms of continents, we may accept their conclusions. That geological evidence exists which seems to favor the existence of a former continent, Antarctica, is claimed on high authority. If this becomes well established we may well explain the distribution of Galaxias with reference to it. But we cannot, on the other hand, regard the anomalous distribution of Galaxias alone constituting proof of shore connection. There can be no doubt that almost every case of anomalies in the distribution of fishes admits of a possible explanation through "the slow action of existing causes."
Real causes are always simple when they are once known. All anomalies in distribution cease to be such when the facts necessary to understand them are at our disposal.
FOOTNOTES:
[22] Hæmulon.
[23] Calamus.
[24] Clarion Island and Socorro Island.
[25] A few Mexican shore fishes, Chætodon humeralis, Galeichthys dasycephalus, Hypsoblennius parvipinnis, have been wrongly accredited to Hawaii by some misplacement of labels.
[26] The dragonets (Callionymus) are shore fishes of the shallowest waters in Europe and Asia, but inhabit considerable depths in tropical America. The sea-robins (Prionotus) are shore fishes in Massachusetts, semi-bathybial fishes at Panama. Often Arctic shore fishes become semi-bathybial in the Temperate Zone, living in water of a given temperature. A long period of cold weather will sometimes bring such to the surface.
[27] "Introduction to the Study of Fishes."