Tertiary. | PALAONTOLOGY OF VICTORIA. (Mammalia, 
to refer them to their true genera from such materials, I propose to 
use provisionally the word Ce/otolites as a generic term for such 
fossil Cetacean Ear-bones as I have to describe. These Ear-bones, 
or Tympanic bones, are always scroll-like, slightly resembling a 
Bulla or a Cowry shell ; very thick and rounded on the lower and 
seemingly involute inner side, but thin, inarched, and scroll-like on 
the outer side to the upper edge, which alone forms the junction 
with the adjacent bones of the head (the Tegmen tympani and pars 
mastoidea), accounting for this edge in the fossils being always 
broken, as the substance of this particular bone is not only excessively 
dense, but very brittle. The same considerations which were relied 
upon to distinguish the four English Tertiary species, the Balena 
afinis, B. definita, B. gibbosa, and B. emarginata, would indicate 
three or four species in our Waurn Ponds quarry. 
All our Victorian Ear-bones are generically distinct from the 
English ones in the division of the internal cavity into two depres- 
sions, a posterior deeper, and an anterior shallower one, by a thick 
swelling from the involute part, and also by the hinder portion 
being more bilobed. My own impression is that they belong to 
Ziphioid Whales ; and long, flat, dense bones found in the same 
strata with them I believe to be remains of the dense, long flattened 
bones of the snout of the same creatures. 
Pirate LIV., Fria. 1. 
CETOTOLITES LEGGEI (McCoy). 
Drscriprion.— Depressed, pyriform; posterior end broad, not indented or 
notched; anterior narrow end obtusely rounded; under side flattened, slightly 
convex, with a very shallow, wide mesial depression near the posterior end, but not 
extending to the margin, which is left prominent and unsinuate; upper side with 
the tympanic cavity small, greatly encroached on from the inner side by the very 
large tumid, regularly convex, posterior portion of the involute inner side, which in 
section forms nearly three-fourths of a circle and occupies exactly two-thirds of the 
greatest transverse diameter of the whole bone at its greatest convexity ; the pos- 
terior third of the external over-arching wall very thick, obtusely rounded at the 
edge and only raised enough to define a shallow cavity, which is almost filled by the 
large broad oblique extension from the middle third of the pyriform involute outer 
ae a 
