Beaked Whales. oF 
varies ; all the latter being generally free in Mesoplodon, whereas 
in Hyperoédon the whole of them, and also the first dorsal, are 
united. The flippers are situated higher up than in the Sperm- 
Whales. 
Of the existing genera, Ziphius, as represented by Cuvier’s 
Beaked Whale (7. cavirostris), has a pair of moderate-sized conical 
teeth in the front of the lower jaw; and in the skull the pre- 
maxillary bones around the nostrils are expanded into forwardly- 
curving crests, of which the right is the larger. Small tuberosities 
are developed on the maxilla at the sides of the root of the beak. 
In Mesoplodon the single pair of lower teeth is generally placed 
some distance behind the apex of the lower jaw ; and there are no 
tuberosities on the maxilla; in one kind, M. layardi, the teeth 
(fig. 12) assume a strap-like form, curving over the beak, so that it 
Bre. 1. 
The Left Periotic (Petrosal) Bone of a Beaked Whale (Mesoplodon bidens), 
to show the type characteristic of the family. Natural size. 
is difficult to understand how the mouth can be opened. Berardius 
arnuxt is characterised by the possession of two pairs of moderate- 
sized lower teeth ; it inhabits the New Zealand seas. 
Mesoplodon is found fossil, in association with the allied 
Choneziphius, in the Red Crag. Mioziphius, Cetorhynchus, and 
Paleoziphius are extinct genera, of which the third has the 
dentition complete. 
Among the specimens exhibited are two half-casts of Sowerby’s 
Beaked Whale (Mesoplodon bidens), made from specimens taken 
off Bergen, Norway. There is alsoa cast of the head of the same 
species, made from a male stranded on the Island of Karmoe, 
Norway, on the 29th August, 1895, and described and figured in the 
“ Bergens Museums Aarbog’”’ for 1897. All these three specimens 
were presented by the Bergen Museum. A skull from Aberdeen- 
shire, presented in 1908, is shown in the table-case, In the same 
