Notice of Dr. Warren's Mastodon Giganteus. 369 
' There are 7 cervical vertebra, 20 dorsal, 3 lumbar, and 5 sa- 
cral. The ribs are twenty in number, 13 true, and 7 false. 
From the 6th to the 11th their length is between 52 and 543 
inches. The first has more the appéarance of a clavicle than a 
nb, and is 28 inches long. Bearing on the number of ribs, Dr. 
Warren observes, (p. 31,) 
“The last two false ribs on the right side are co-ossified for the 
space of 8 inches ;—the result of a fracture near their vertebral attach- 
ments: the union of these ribs, at its broadest part, measures 8 inches. 
lese bones are perfectly smooth within, and without are quite strong, 
atthe place of union and massive. This fracture is of great import- 
, as he union is verified the remark of Cuvier, who found only 
19 ribs, but stated that there would, in his opinion, be hereafter found 
‘wenty—a fact entirely established in this specimen, first by the articu- 
‘ar surface on the side of the 20th dorsal vertebra; and second, by the 
Co-ossification of the 19th and 20th ribs.” 
_ After describing the several bones throughout the structure, the 
author treats at considerable length of the characters of the teeth. 
Those of the elephant are first described by way of comparison, 
their number (twenty-four exclusive of the tusks), composition, 
and form being considered. On taking up the odontography o 
"€ Mastodon, the author commences with some general observa- 
tions, and then proceeds to a minute account of each of the teeth 
iM succession, Omitting the mass of details, we cite the follow- 
ing from his General Remarks, pages 61 to 64: 
“While the teeth of the elephant are, as already said, composed of 
pre kinds of hard matter, dentine, enamel, and cement, those of the 
astodon giganteus are constituted principally of two of these substan- 
Ment, by its perpendicular interposed layers, constitutes a substantial 
Part of the body of the tooth, as well as a protecting covering to its 
surface. A great portion of the Mastodon tooth is formed by dentine. 
; © Mamillary eminences, or mastoid projections also have a basis : 
the same substance, but they are invested with a covering of enamel, 
| i ion, measures from the sixth to the 
possess 
earth of an inch in thickness. In teeth which have been worn, the 
: nd 
. ; h ican Elephant. 
teus, nie lozenge-shaped ridges of the Alncan, roe 
The number of the teeth was long involved in mystery. The gen- 
Us of Cuvier Sissel the wit to a knowledge of their number, differ- 
and development. He advanced no farther in the path he had 
°Pened than to the fourth, or, at the utmost, fifth tooth; making the 
48 
‘Stoonp Szams, Vol. XV, No. 45.—May, 1853. 
