158 REPORT—1874. 
Labyrinthodon, Owen. 
Choane. Large, oval, distant. Teeth (disposition). Maxillary, at least one large 
tusk, succeeded by small serial teeth ; palato-vomerine, a transverse row of a few 
small teeth between choana and anterior palatine foramen, one or more tusks in 
front of choana, a short row of small teeth internal to it, the rest unknown; 
mandibular numerous, subequal, a short inner series of one or two tusks adjacent 
to the symphysis. Teeth (structure). Slender, tapering to the apex, somewhat 
elliptical at the base, conical above ; the lower third is fluted; the internal struc- 
ture is similar to that of Mastodonsaurus, but the folds of dentine are fewer in pro- 
portion to the diminished circumference of the tooth. Cranial sculpture. Radiate, 
consisting of ridges enclosing flat spaces; elsewhere tuberculate and irregular; a 
well-defined lyra (imperfectly preserved) and maxillary groove. 
Measurements of Teeth (from Owen’s ‘ Odontography’). Wo 
Anterior mandibular tusk, diameter qc: ss css +s vo a oa sfebeielers 5 
DosteMor Mandi ar ibeStliMitsy me i isle ieee: «(ole \-->/s 010 «less u/s nino 125 
Maxillary tusk, Dig hn, incica cca ce PARDEE, ORT. .cr0 2 
Serial maxillary teeth, et 0 Hoey PEE e 5 ciao ot 027 
Serial maxillary teeth, length (imperfect). ........0.+.ceesseees 12 
L. LEPTOGNATHUS, Owen. 
Locality. Keuper Sandstone of Warwick. 
References. Owen, Trans. Geol. Soe. vol. vi. pl. ii. p. 503, pl. xliii. figs. 1-3, pl. xliy. 
figs. 7-9 [1842].—Jd. Odontography, p. 207, t. lxiii. a. figs. 1, 1’, 2, 2', 3, 
t. lxiii.p [1840-45].— Von Meyer, Palaontologie Wiirttembergs, p. 36 
[1844].—Miall, Q. J. Geol. Soc. vol. xxx. pp, 425, 430 [1874]. 
Diadetognathus, Miall. 
Mandibular articulation. A large postarticular process, concave above; no in- 
ternal articular buttress. Teeth. Much compressed, antero-posteriorly, at the base, 
so that in section they present the form of a rectangle, with the long sides perpen- 
dicular to the axis of the jaw; above, the teeth gradually become conical; the 
external surface exhibits numerous striz, but no conspicuous ridges; the dentine 
is much folded, but there are many intricacies of arrangement which no folding, 
however complicated, can explain; no pulp-cavity is visible, but the upper part of 
the tooth has not yet been microscopically examined. Cranial sculpture. Similar 
to that of Mastodonsaurus, but less sharply defined. 
D. VARVICENSIS, Miall. 
Locality. Keuper Sandstone of Warwick. 
References. Miall, Q. J. Geol. Soc. vol. xxx. pp. 425, 482, fig. 3, t. xxvii. fig. 3, 
t, xxviii. [1874]. 
Dasyceps, Huxley. 
Skull (figure). Triangular, rounded in front, slightly convex on the sides, with 
projecting epiotic cornua and large truncated postero-lateral expansions ; a facial 
“fontanelle.” Orbits. Small, round, distant, placed far back. Palatine foramina. 
Relatively small, distant. Haternal nasal foramina. Small, round, distant, un- 
usually far back. Choane. Large, oval, marginal, unusually far back. Parietal 
foramen. Large, round, but little posterior to the orbits. Teeth. Maxillary, 
“ pointed, much curved, and about a quarter of an inch long, their bases having a 
diameter of three fortieths of an inch. They are directed outwards, their curved 
sides being downwards and inwards (in the natural position). They are anchylosed 
to the margins of the jaw, which exhibits no alveolar groove. Their bases are 
longitudinally striated, and they present apparently a wide pulp-cavity; but I can 
say nothing respecting their minute structure, as I did not feel justified in detaching 
any of the few which remain. Obscure traces of teeth are seen in the rest of the 
