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Notice of Dr. Warren’s Mastodon Giganteus. 371 
The fact well established in regard to the elephant, seems to afford 
presumption, that besides the great intermaxillary tusks of the Masto- 
on, there may be others in the upper or lower jaw, which appearing 
at an early period of life, are, in the greater number of instances, lost 
before the animal has advanced far in its existence. 
_ In the present specimen of the Mastodon, there are two tusks in the 
Upper and one in the lower jaw on the left side. Two undoubtedly 
existed in the lower jaw, at an early period of life, as the relic of the 
right cavity is perfectly distinct, retaining a depth of an inch anda 
If, and nearly its original diameter. 
The Superior Tusks.—The tusks of the upper jaw were ten feet and 
middle portion, rather more than two feet, has crumble : 
— portion, of about the same length with the anterior, is broken 
in one diameter than in the other, making the largest seven inches and 
ahalf. The bases are surrounded external! y by circular elevations, at 
first two inches distant from each other, bat gradually increasing in 
distance, until, at about two feet from the extremities of the bases, they 
disappear entirely. 
he tusk is composed of lamin which at the internal extremity of 
me socket, are not more than a line in thickness. ‘These laminze in- 
crease in number as we advance from the butts, so that where the tusk is 
Sues from its socket at the distance of rather more than two feet from the 
ome extremity, the internal cavity has diminished from seven inches 
Ndiameter to two by two and a half. The plates into which the tusk 
has Separated in drying are generally an eighth of an inch in thickness, 
some of them nearly an inch. The external surface has a brown ap- 
oma the layers which have been recently uncovered are of a 
er color, F 
The following analysis of a portion of the tusk has been kindly fur- 
~l@d me by Dr. Chas. T. Jackson: 
Animal matter (cartilage), - . ae % 
__ Phosphate and Mee of lime, fluorid of calcium, é&c., gor 
, Water, F ; ‘ : : . eae 
" 100-0 
Glass was etched with the fluorine. The constituents of the tusk are 
Phosphate of lime, carbonate of lime, fluorid of caleium, phosphate 
* : 
ne of the circular marks seen at the 
Posterior extremity. The. point anteriorly is worn away for the space 
inches on one side, as is general 
“yy? Proboscidian family. . é bie 
“hen the tusks were frat discovered, they lay with their oon tad 
SutWards, their points approaching each other; having apparently tu 
