246 
Miscellaneous. 
BASILOSAURUS. 
The following is an extract from a letter from Prof. J. Muller to 
Mr. A. Retzius, dated Berlin, March 24, 1847 : — 
“ The Hydrarchus, Koch, found in the tertiary formation in Ala- 
bama, is identical with Harlan’s Basilosaurus and Owen’s Zeuglodon 
cetoides"^. The crowns of the teeth, with which Owen was not ac- 
quainted, have a great resemblance to those of the Seal ; in the max- 
illary teeth they are cutting and many-pointed ; most of the maxillary 
teeth have double roots, but the anterior has, as in the Seals, only a 
single root. In the anterior part of the jaw are found conical curved 
teeth, viz. an incisive and a canine, at least this is the case with the 
under jaw. 
“ As such teeth as those which are found in the Hydrarchus oc- 
cur in the tertiary formation in Malta, we may conclude that this 
animal belongs likewise to the tertiary formation of that island. 
“ I think I can positively show that the Hydrarchus is not a rep- 
tile, but a mammal belonging to a peculiar extinct family. It has the 
ear formed as in the mammals, viz. a helix and a tympanic bone as 
in the Whales. It has moreover two occipital condyles, and in the 
whole formation of the cranium no trace of reptile structure occurs, 
but on the contrary everything is as in mammals. 
“ The vertebral column is very peculiar in its structure. The cer- 
vical vertebrae, probably more numerous than in any other mammal, 
are without perforations in their transverse processes ; the ribs are 
only attached to the transverse processes of the vertebrae ; at the 
central and posterior part of the column the bodies of the vertebrae 
are unusually long, and must both at the anterior and posterior part 
of the extremities have been cartilaginous, inasmuch as we find here 
beneath the bony shell a mass of pure stone, while the central part 
of these vertebrae consists wholly of hon^.'^—Silliman's Journal for 
Nov. 1847. 
Additional Note on a paper on Porcupines. 
By J. E. Gray, Esq., F.R.S. &c. 
In my former paperf I was unable to give the country of Acanthion 
Cuvieri. Mr. Frazer has since brought a skull and two living spe- 
cimens of this species from Algiers ; the latter are now in the Gar- 
dens of the Society, and Mr. Whitfield has brought others from the 
Gambia. In the number of the Journal of the Asiatic Society of 
Calcutta for August 1847 just arrived (p. 772. t. 32), I observe that 
Mr. Hodgson has described a new' species of Indian Porcupine under 
the name of Hystrix alopceus, called AnchoUa by the natives, which 
is certainly an Acanthion, and most probably my A. Hodgsonii ; if so, 
the latter name will have the priority, as having been published in 
July. — From the Proceedings of the Zoological Society, Nov. 9, 1847. 
*■ Phocodon, Agassiz. Sqiialodon, Grateloup, in Leonhard and Bronn’s 
Jalirbuch fiir Mineralogie, 1841, p. 830. 
t Ann. Nat. Hist. vol. xx. p. 349. 
