Fl) een ee ee 
Botany and Zoology. 445 
which appears to correspon nd with the internal menta tal foramen. of the 
Iguana. Just posterior to this foramen there is a deep vascular groove, 
which in the ail condition of the specimen may have proceeded 
from another fo’ 
The teeth in ao relation to the dental bone, are placed upon the 
inner side, and rest against the alveolar border, which rises in a parapet 
external to them. Whether the parapet is supported by abutments be- 
tween the teeth, as in Megalosaurus, I cannot certainly ascertain from 
the inner side of the jaw being so closely adherent to the matrix. The 
dental bone, if it be considered complete in its length in the spetimen, 
is capable of containing a series of twelve —— posterior to and inclu- 
ding that situated most anteriorly in the foss 
As the teeth were worn away or broken off they were replaced by 
Others produced at their inner side, as is indicated in the specimen by 
& young tooth, —— is situated internal to, and is concealed by, the 
largest mature t 
The ihn Se crowns of the fully protruded teeth are exoreing at their 
base for several lines above the alveolar border of the j 
compressed, conoidal, and recurved, but compared with a we of Me- 
galosaurus they are not so broad, compressed, nor recurved, and they 
are more convex externally, and a are less so internally. They resem- 
ble much in form those of the recent Monitor ornatus, but are less con- 
vex internally. 
he transverse section of the crowns of the teeth, except that of 
the first, is antero-posteriorly elliptical, with the inner side less convex 
and the extremities acute and in most instances slightly incurved. 
The anterior and posterior acute margins of the crowns are minutely 
Crenulated ; and the crenulations commence just below the tip and de- 
scend as far as the enamelled base 
In comparison with the teeth of “Clepsysaurus sn er those 
of the fossil under examination are broader and more compressed, an 
except the first one of the series, present an acute, cteingpilied margin 
anteriorly and 9 0S page in the former animal they are acute 
and crenulate only posteriorly.—[We omit part of the details. ] 
rom the extraordinary PE depth of the dental bone above de- 
Scribed to its length, and from its northern locality, I have erm for 
the menting lacertian to which it belonged the name of Bathygna- 
realis. 
This interesting fossil is the second authentic dimiiveaey of saurian 
bones in the New Red Sandstone Formation of North America ; the 
first being those found near Hassac’s Creek, in Lehigh Co., Pennsylva- 
= by Dr. Joel Y. Shelley, and described by my friend Mr. Isaac Lea, 
ader the name of Clepsysaurus Pennsylvanicus.t 
“In relation to the exact locality and geological position of the Bathy- 
8 hus borealis, Mr. J. W. Dawson has furnished me with the following 
“The fossil was found at New tetedien, on the northern side of the 
Island, Lowe satagee to the depth of nine feet in red sandstone, with calca- 
attached to 
ment, similar to the matrix to the fossil. The total 
* bocMSi waka WBE + Ibid, v., 171, 205 ; Jour, Ac. Nat Sci, ii. 
