“The head, between one-fourth and one-fifth of the total length, allies it to the shorter-headed species. From the _B. australis_ the number of dorsal vertebræ, and the colour and shortness of the baleen, distinguish it; and no doubt other features will be brought out when we are acquainted with the Cape species. The dorsal serration is not known to occur in any species of the genus _Balæna_, though said to be characteristic of the _A. gibbosus_, whose characters I have just given. “Two _Balænæ_ have been described as inhabiting the North Pacific Ocean, _Balæna Sieboldii_, Gray (Catal. Cet. 1865, p. 96), and _Balæna cullamach_, Chamisso (Nov. Act. Acad. Cæs. xii. p. 251, tab.) “Both have been established on figures carved by the natives, of the Japanese and Aleutian Islands respectively, the former under the supervision of a naturalist, the traveller Siebold. The carving of the _B. cullamach_, judging from the figure given by Chamisso, can but doubtfully represent any species; but if the species exist, it will rest on the following diagnosis of its describer:—‘Rictu amplo forma litteræ S curvato, elasmiis maximis atro-cæruleis, spiraculis flexuosis, in medio capite, tuberculo in apice rostri (ex imagine), pectore pinnisque pectoralibus albis, dorso gibboso sexpinnato.’ “These are, however, true _Balænæ_. A species of _Agaphelus_ exists in the Kamtschatkan seas, according to Pallas, who, however, derives his information solely from wooden models made by the Aleutian Islanders. This is not sufficient basis for an introduction to the scientific system; yet Pallas indulges in applying to it the name _Balæna agamachschik_. The pectoral limb of this species is said, however, to be white, with the underside of the flukes, characters not found in the _A. glaucus_. Dr. Gray has already (Cat. Brit. Mus.) indicated that this, if reliable, indicates a genus unknown to him. “The _Agaphelus glaucus_ is the Grey Whale of the coasts of California. Two specimens have been examined by my friend Wm. H. Dall, of the scientific staff of the U. S. Russian-American Telegraph Expedition, one of them near Monterey; and descriptions, as complete as the state of the specimens would allow, were made. “These, which were sent to the Smithsonian Institution, and placed in my hands by Prof. Baird, are quite sufficient to indicate a Whale of a species hitherto unnoticed, and to render certain its future identification. “Dorsal vertebræ and ribs 13; lumbar and caudal (those in the fluke cut off with it) 28. Scapula, breadth and height not very different, with a short broad coracoid process; its head opposite first rib. Apparently only four fingers, of which the second is the longest. 145 laminæ of baleen on each side, the longest 18 inches long; colour bright yellow.”—_Cope_, _Proc. Ac. N. Sc. Philad._ 1868, p. 226. Family 3. MEGAPTERIDÆ. _Humpbacked Whales._ Megapterina, _Gray_, _l. c._ p. 113. Megapteridæ, _Gray_, _Synops. Whales & Dolph._ p. 2.