234 CETACEA 
in the air to turn round their heads and look about them, taking 
the water head first, and not falling helplessly into it sideways like 
the larger whales. The full-grown whale is 30 feet long by 20 
feet in circumference, and vields two tons of oil besides two hundred- 
weight of spermaceti. . . . Their ordinary food consists of a bluish- 
white cuttle-fish, six inches long by three inches in circumference, 
and pointed towards the tail... . They evidently have a great 
depth to go to find them, judging from the length of time that 
they remain away, and from the long heavy blasts they make on 
coming to the surface again.” 
Periotic bones of Hyp roédon are found in the Red Crag of 
Suffolk, presenting no character by which they can be specifically 
distinguished from those of the common existing species. 
Ziphius.i—A single conical tooth of moderate size on each side 
of the mandible close to the anterior extremity, and directed 
forwards and upwards. Skull with the premaxille immediately in 
front of, and at the sides of the nares expanded, hollowed, and with 
elevated lateral margins, the posterior ends rising to the vertex and 
curving forwards, the right being considerably more developed than 
the left; the conjoint nasals forming a strongly pronounced sym- 
metrical eminence at the top of the cranium, projecting forwards 
over the nares, flat above, most prominent and rounded in the 
middle line in front, and separated by a notch on each side from 
the premaxille. Anteorbital notch not distinct. Rostrum (seen 
from above) triangular, gradually tapering from the base to the 
apex; upper and outer edges of maxille at base of rostrum raised 
into low roughened tuberosities. Mesethmoid cartilage densely 
ossified in adult age, and coalescing with the surrounding bones of 
the rostrum. Vertebre: C7,D10,L10, C22; total 49. The 
three anterior cervical vertebrxe united, the rest free. 
The type of this genus is Z. cavirestris of Cuvier, founded upon 
an imperfect skull picked up in 1804 on the Mediterranean coast 
of France, and described and figured in the Ossemens Fossiles under 
the impression that it was that of an extinct species. Many other 
individuals have, however, been subsequently met with in various 
parts of the world, from the Shetland Islands to New Zealand, all 
referable to the same genus, if not to the same species ; although, 
as is usual in such cases, they have mostly been described under 
different names, the so-called genera Petrorhynchus and E'piodon 
being probably referable to the type species. 
It is quite probable that some of the Physcteroid teeth from the 
Crag deposits mentioned on p. 251 may be referable to Ziphius, 
Mesoplodon.-—A much compressed and pointed tooth in each 
Cuvier, Ossemens Fossiles, 2d ed. vol. v. p, 352 (1828). 
* Gervais, «fru. Sei. Nad. sér, 3, vol. xiv, p. 16 (1850). For the very com- 
plicated synonymy of this genus, see Trans. Zool. Sov. vol. viii. p. 208, 
