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MEYER, REPTILES IN THE COAL FORMATION. 55 
maintaiming the same direction backwards and outwards, would re- 
present the process, which in the crocodile, of a cartilaginous con- 
sistence, is attached to the posterior horn. The rhombic shape of 
the body also reminds us of the hyoid bone of the tortoises, the 
horns of which, however, are attached to the body more in a rib-like 
manner. The interpretation of this apparatus as the hyoid bone 
seems more probably correct, since in its vicinity traces of external gills 
exist, which appear in the form of a double oval arch formed of small, 
oblong laminze, pectinated on the inner side. This hyoid bone also 
recalls, in the form of the body, the bones which were found with the 
skull of the Mastodonsaurus, so that even from this point of view 
the Archegosaurus would offer a close relation to the Labyrinthodon. 
In confirmation of this statement the reviewer would refer to the 
‘Contributions to the Paleontology of Wurtemberg*,’ published by 
Plieninger and him, in which in tab. 3, fig. 1, 2, a rhombic bone 
resembling the body, and im tab. 4, fig. 1, 2, a wing-shaped bone 
resembling the right posterior horn of Archegosaurus are figured. 
The large size of the hyoid bone must have given to the neck of 
the Archegosaurus a breadth equal to that of the head. The animal 
has been much shorter in the body than the crocodile ; of the tail 
nothing remains. Some small thin bones are compared to the coracoid 
bones anchylosed to the clavicle and to the scapula of the Proteus, 
The remains of the extremities leave no doubt that the Archegosau- 
rus was provided with actual hands and feet, terminating in distinct 
toes. But these limbs were weak, serving only to swim or creep. 
The peculiarities of the skeleton correspond to those of the skin, 
which consisted of long, narrow, wedge-shaped, tile-like, horny scales, 
arranged in rows, which met on the ventral side in Archegosaurus 
Decheni at right angles, in 4. medius in a curve. 
The Archegosaurus was consequently most nearly allied to the 
Labyrinthodonts. The latter, as is well known, were at first considered 
by Owen as Batrachians, whose structure approached to that of the 
frog, whilst the reviewer, who had a much richer store of materials 
for mvestigation at command, inclined to the opinion that they were 
rather Saurianst. Owen is now also disposed to the same view, 
considermg the Labyrinthodonts as Saurians arrested in their deve- 
lopment (Genesis), on the level of the Batrachians, and which have 
the same import (Bedeutung) for the Saurians, and occupy the same 
systematic place among them, that the Batrachians do in the whole 
class of Reptilest. With this idea, the type handed down to us in 
* Beitrage zur Paleontologie Wurtembergs. + Ibid. 
t The following passages contain a more accurate statement of Professor Owen’s 
original views of the affinities of the Labyrinthodon than is given above. ‘‘ The 
modifications of the jaws, and more especially those of the bony palate of the 
Labyrinthodon leptognathus, prove the fossil to have been essentially Batrachian, 
but with affinities to the higher Sauria, leading in the form of the skull and the 
sculpturing of the cranial bones to the Crocodilian group, in the collocation of 
the larger fangs at the anterior extremities of the jaws to the Plesiosaurus, and in 
one part of the dental structure, in the form of the episternum, and the biconcave 
vertebrze, to the Ichthyosaurus.”—Report on British Fossil Reptiles in the Report 
of Brit. Assoc. for 1841, p. 185. And subsequently, p. 188: “ Thus all these 
