OWEN.—CLASSIFICAION OF REPTILIA. 79 
from the nature of the cutaneous coverings equally fail to determine the class- 
characters of Batrachia as contra-distinguished from Reptilia. It is true that all 
existing Batrachia have a scaleless skin, or very minute scales (Cecilia), but not 
all existing reptiles have horny scales. The crocodiles and certain lizards show a 
development of dermal bones similar to that in certain placoid and ganoid fishes. 
This development is greater, and the resemblance is closer, in those ancient forms 
of Reptilia which exhibit in their endo-skeleton unmistakeable signs of their 
affinity to ganoid fishes and Batrachia. In a survey, therefore, of the present 
known forms of cold-blooded, air-breathing Vertebrates, recent and fossil, Prof. 
Owen could not define any real and adequate boundary,for dividing them primarily 
into two distinct classes of Batrachians and Reptiles. As little was he able to 
point out a character dividing the air-breathing from the water-breathing Hama- 
tocrya—the reptiles from the fishes. In the present communication the author 
drew an arbitrary line between Lepidosiren and Archegosaurus, and proposed to 
begin his review of the ordinal groups of Reptilia, or air-breathing Heematocrya, 
with that of which the Archegosaurus was the type. 
Order I. Ganocephala.—For this group or order he proposed the name of 
Ganocephala (vyavos, lustre, xepadn, head), in reference to the sculptured and ex- 
ternally-polished or ganoid bony plates with which the entire head was defended. 
These plates include the “ postorbital” and “supertemporal” ones, which roof 
over the temporal fossz. No occipital condyles. The teeth have converging in- 
flected folds of cement at their basal half. The notochord is persistent ; the ver- 
tebral arches and peripheral elements are ossified ; the pleurapophyses are short 
and straight; pectoral and pelvic limbs, which are natatory and very small; 
large median and lateral “throat-plates;’ scales small, carinate, sub-ganoid ; 
traces of branchial arches. The above combination of characters gives the value 
of an ordinal group in the cold-blooded Vertebrata. The extinct animals which 
manifest it were first indicated by certain fossils discovered in the spherosideritic 
clay-slate forming the upper member of the Bavarian coal-measures, and also in 
splitting spheroidal concretions from the coal-field of Saarsbruck, near Treves; 
these fossils were originally referred to the class of fishes (Pygopterus Luczus, 
Agassiz.) Buta specimen from the “ Brandschiefer ” of Miinster-A ppel presented 
characters which were recognised by Dr. Gergens to be those of a Salamandroid 
reptile.* Dr. Gergens placed his supposed “Salamander” in the hands of M. 
Hermann von Meyer for description ; who communicated the result of his exami- 
nation in a later number of the under-cited journal.+ In this notice the author 
states that the Salamander-affinities of the fossil in question, for which he pro- 
poses the name of Apateon pedestris, ‘‘are by no means demonstrated.”{ “ Its 
head might be that of a fish, as well as of a lizard, or of a batrachian.” ‘ There 
is no trace of bones of limbs.” M. von Meyer concludes by stating that, ‘in order 
* “Mainz, Oktober, 1843.—Im dem Brandschiefer von Miinster-Appel, in Rhein-Baiern, 
habe ich in vorigen Jahre einen Salamander aufgefunden. Gehort dieser Schiefer der 
Kohlen-formation? in diesene falle wire der Fund auch in anderen Hinsicht interressant.” 
Leonhart und Bronn, Neues Jahrbuch fiir Mineralogie, &c., 1844. p. 49. 
t+ Ibid. 1844, p. 336. 
=“Ob das—Apateon pedestris—ein Salamander-artiges Geschépf war, ist keineswegs 
ausgemacht.” 
