334 SIR R. OWEN ON A LABYRINTHODONT AMPHIBIAN. 
the cranial bones. This fossil is figured in plate xx. figs. 13-20, 
in my ‘Catalogue of the Fossil Reptilia of S. Africa, in the British 
Museum’ (4to, 1876, p. 67). 
A somewhat larger fossil skull (3 inches 6 lines in length) preserved 
in the Museum of the Imperial Society of Naturalists of Moscow, 
and described by Fischer de Waldheim under the name Rhino- 
saurus Jasikovii, I believed, from its shape and the close correspon- 
dence of the granulate ganoid superficies of the cranial bones, to 
belong to the labyrinthodont rather than to the saurian order. 
Fischer notes, in his account, that this fossil, “‘quoique découvert 
dans le Gouvernement de Simbirsk, est sans indication précise de 
localité”*. If this fossil should yield the structure of the bony 
palate, and the occipital articulation with the atlas, 7.¢., whether by 
one or two condyles, its affinity or otherwise to the Labyrinthodonts 
would be determined. 
The Cape Petrophryne revealed the double condyle tT, but not 
the characters of the bony palate. 
The fossil of which I have now the pleasure to submit a deserip- 
tion, supplies the palatal character; but the occipital part of the skull 
is wanting. 
This cranial specimen (Plates XVI. & XVII.) was obtained, in a 
fractured condition, by Heer Swanopol, from the Trias of a locality 
called Beersheba, and was deposited by him in the Bloemfontein 
Museum. The authorities have confided it to Dr. Exton, of the 
Orange Free State, S. Africa, in order to be submitted to me with 
other fossils, including T'ritylodon. 
After readjustment of those parts of this fossil skull of which 
the true relative positions could be determined, the result 
was the proportion of the facial division, including the external 
nostrils (Plate XVI. figs. 1, 2, n.) and orbits (2b. 0), with a corre- 
sponding part of the lower jaw (id. 29-21), thereto cemented by 
matrix, which forms the subject of the figures now submitted 
to the Society. In one of these (Plate XVII. fig. 1) are shown 
the characters exposed by careful removal of matrix from the bony 
palate. Detached portions of the mandible, and a few other 
fragments have helped in the determination of the affinities of the 
fossil. 
The proportions of breadth to length, with general flatness, of the 
skull being batrachoid rather than saurian, my first step was to 
submit one of the teeth to the microscopic test. For this purpose L 
selected the hinder palato-vomerine tusk, from which the apical half 
of the crown had been broken away (Plate XVII. fig. 1, mo). 
The subjoined drawing of the section {, magnified 20 diameters 
(Plate XVII. fig. 2), shows the decisive character of the laybrinthic 
* «Bulletin de la Société Impériale des Naturalistes de Moscou,’ tom. xx. 
1847, p. 14. 
T See Cat. Foss. Rept. 8. Africa, plate xx. fig. 16. 
t In this the letter d indicates the entry of the ‘dentinal’ process of the 
tooth-pulp, the letter ¢ the entry of the alternating process of the ‘ cement,’ 
from the capsule of the tooth-matrix. 
