39Q 



REPTILES 



suggest that these animals were related to the early mammal-like rep- 

 tiles (p. 539). *Limnoscelis, however, was a particularly primitive form, 

 and may have been partly aquatic in habits. 



Other rather later cotylosaurs were larger forms, such as *Diadectes 

 (Fig. 222) and *Bradysaunis and other 'pareiasaurs' from the Permian 

 and Triassic of Europe, Africa, and America. These were up to 10 ft 



Limnosce'is 



Captorhinus 



Labidosaurus 



Diadectes 



Triassochelys 



Bradysaurus 

 Fig. 222. Skulls of various early reptiles. After Romer and various authors. 



long and probably carried the body well off the ground, the limbs 

 being held underneath the body and showing some reduction of 

 specialized digits. This, together with the large size of the animals and 

 their specialized teeth, suggest that they may have been one of the 

 first of the many types of large herbivore to appear on the land (see 

 p. 429). In some of them the skull developed grotesque protective 

 protuberances, a feature recalling similar later developments in 

 reptiles (Ceratopsia, p. 426) and mammals (amblypods, p. 717). A 

 characteristic structural feature was the presence of an otic notch low 

 down on the side of the skull. This distinguishes the pareiasaurs from 

 the more mammal-like forms and suggests affinity with some of the 

 other reptilian descendants of the early cotylosaurs. These cotylo- 

 saurs multiplied and became very diversified throughout the 45 million 



