IQ34 



CLASS AMPHIBIA. 



than in the Archegosauridce. The vertebral centra are disk-like, 

 and may perhaps be embolomerous. Loxomma (fig. 963) occurs 

 in England in the Carboniferous, but has also been recorded 



Fig. 964.— Dorsal surface of the skull of Anthracosaurus Russelli; from the Carboniferous 

 of England. One-sixth natural size. (After Atthey.) 



from the Permian of Bohemia. The large size of the orbits is 

 well shown in the figure ; another characteristic feature being the 

 absence of a postglenoidal process to the mandible. The ventral 

 scutes are unknown, and if it be eventually found that these are 

 wanting, this genus should perhaps form the type 

 of a distinct family. In the typical subfamily 

 Anthracosaurince. the skull (fig. 964) is triangular, 

 and characterised by the small size of the pala- 

 tal vacuities ; while the teeth are subcylindrical. 

 The type genus Anthracosaurus occurs, as its 

 name implies, in the Carboniferous, ranging from 

 Britain to the Continent. One of the dermal 

 ventral scutes is shown in fig. 965. The skull 



was also covered with scales or scutes ; and it 



Fig. 965. — Scute of 

 Anthracosaurus. (After 

 Atthey.) 



appears from one specimen that these scutes did 

 not extend over the parietal foramen, which in- 

 duces Dr Credner to consider that the Palaeozoic 

 Labyrinthodonts were provided with a functional parietal eye, of 

 which an aborted rudiment persists in Sphenodon. The imperfectly 



