8. Cat. No. 21248. Skull of a male (?).
9. Cat. No. 83991. Skull.
The five skulls preceding were also collected by Doctor Stejneger in Bering Island in 1882 and 1883.
10. Cat. No. 22069. Skull of a female (?).[37]
11. Cat. No. 22874. Skull.
12. Cat. No. 22875. Bones of an immature individual.
These three specimens were collected and presented by N. Grebnitzki.
13. Cat. No. 142579. A series of photographs of an individual captured in Kiska Harbor, Alaska, September, 1904. Presented by Dr. J. Hobart Egbert.
14. Cat. No. 84906. Photograph of the skeleton of an individual washed ashore at St. Simon Island, Georgia, in 1893, and belonging to Mr. W. Arnold.
In the genus Ziphius, as in other ziphioid genera, a study of the characters of the skull appears to afford the best basis for discrimination of species. We have first to consider whether the North American species is the same as the European and New Zealand species, and afterwards whether the North Pacific species is identical with or distinct from these.