Notice of the Tooth of a Mastodon. 53 
of the same volume. It is not the variety of C. tentaculata, which 
Mich. called C. rostrata in letters to Schk., as these are obviously 
the same, for both are in my herbarium. 
C. rostrata, Mich., is a more stiff and less leafy plant than C. 
ranthophysa, Wahl., and has sessile spikes, while the other has 
_ them’en long exsert peduncles and recurved, and with stamens at 
the apex as Mich. remarked ; and it has a short, hardly acute pis- 
tillate scale, while the other has an ovate, acuminate, and long cus- 
pidate scale but little shorter than the fruit. There can be no doubt 
that the C:. rostrata, Mich. is identified, and is a distinct species. 
Art. VIIl.—WNotice of the Tooth of a Mastodon; by Jerrries 
; yuan, M.D. ~~ 
Tne specimen from which the following description is drawn, 
was deposited in the cabinet of the Boston Society of Natural 
History, by the Rev. Howard Malcom, by whom it was obtained 
at a place called Yea-nan-goung, situated on the banks of the Ira- 
wady river, below Avain Burmah. It consists of a fragment of the 
left lower jaw of a mastodon, containing one molar tooth entire, 
excepting so much as has been worn away by the process of mas- 
tication. As it differs materially from any of which a description 
has been met with, it was thought worthy of a brief notice. 
The jaw is broken at the two ends of the tooth, the interven- 
ing portion being entire. 'The whole specimen is sixteen 
in length, and its circumference around the largest part se sored 
two inches. The tooth measures twelve and a half inches in 
length and four anda half in breadth. At the anterior extremity 
is a portion of a denticule, of which the greater part has been 
ground off ; allowing that this had the same dimensions with 
that which succeeded it, we shall have an additional length to 
the tooth of an inch and a half, making the entire length one’ 
foot two inches. ‘The enamel is a quarter of an inch in thick- 
ness, and its surface is rough from an incrustation of calcareous 
matter. The denticules are eight in number, or nine counting 
the one of which only a small portion remains, and project two 
and a half inches above the alveoli. Each denticule uniformly 
consists of four distinct mammillary points, symmetrically ar- 
ranged. ‘These are all separated from each other by a distinet 
sulcus, the external ones being broad and stout at their base, and 
