INTRODUCTION.
The beaked whales belonging to the family Ziphiidæ are, with the exception of the bottle-nosed whales of the genus Hyperoödon, among the rarest of cetaceans. Of the three genera Mesoplodon, Ziphius, and Berardius, so far as I have been able to ascertain from published records, specimens representing about one hundred individuals are known, and somewhat more than one-half of these belong to the first-named genus. Berardius is the rarest genus, only about fourteen specimens having been collected thus far. The U. S. National Museum contains specimens representing some twenty-five individuals of the three genera, or about one-fourth of the material at present available. Among these are six specimens of the genus Berardius, or nearly half of all that have been recorded thus far.
The most important addition to the knowledge of these whales made during the last quarter century was the discovery of representatives of the three genera Mesoplodon, Ziphius, and Berardius, at Bering Island, in the North Pacific, by Dr. Leonhard Stejneger, whereby the known range of the family was very greatly extended. Two of the forms were described by Doctor Stejneger in 1883, and the third by myself from a skull which he collected. About one-half of the material which the Museum possesses consists of that collected by Doctor Stejneger in Bering Island and that from the same locality presented by Mr. Nicholas Grebnitzki, Russian governor of the Commander Islands.
About six years ago the National Museum received information and specimens from correspondents showing that the range of the three genera found at Bering Island extends to the eastern North Pacific, one genus (Ziphius) having been observed at Kiska Harbor, Alaska, another (Mesoplodon) at Yaquina Bay, Oregon, and the third (Berardius) at St. George Island, Pribilof Group, Alaska, and near Cape Mendocino, California.
On the east and west coasts of the United States the only occurrences of beaked whales known to me are as follows: