I02 THE PERMO-CARBONIFEROUS RED BEDS OP 



reckoned as purely, or even largely, herbivorous. Some are clearly pure car- 

 nivores; others may have included some portion of vegetation in a diet 

 composed largely of hard-shelled molluscs. 



The synoptic statement below will give an idea of the form of the 

 teeth in the different groups and their supposed food habits ; but besides the 

 forms mentioned there were numerous smaller reptiles, with sharp, conical 

 teeth, which can only have been carnivorous or insectivorous. 



Pei.ycosauria. 

 Poliosaurirla;. 

 Clepsydropida; (Sphenacodontidoc). 



All with sharp and conical teeth, which were recurved in some forms, and with more or less sharp 

 and even serrate cutting-edges. Maxillary and incisor tusks enlarged in certain forms, some- 

 times to relatively great size. Raptorial; carnivorous. 

 Edaphosauria. 



Edaphosaurida;. 



Teeth on the edges of the jaws sharp and conical; incisor teeth somewhat chisel-shaped; strong 

 crushing-teeth developed on plates on the dentaries, pterygoids, and palatines. The crushing- 

 teetli with short, sharp points when young, but wearing blunt or flat. Molluscivorous (duro- 

 phagous). 



COTYLOSAURIA. 



Limnoscelidce {Limnoscelis). 

 Labidosauridoe. 



Teeth all sharply conical; enlarged incisors in the premaxillary (sharply inclined backward in 

 Labidosaurns); anterior cheek-teeth somewhat larger than the posterior; incisor-teeth of the 

 lower jaw larger than the posterior ones, but smaller than those of the premaxillary. Carnivo- 

 rous; raptorial. 

 CaptorhinidEB. 



Incisor-teeth of the upper jaws elongate, conical. Cheek-teeth short, conical, and strong, wearing 

 to a flat surface; clusters of teeth on the maxillaries and dentaries. The median ones of the 

 outer row of teeth on the maxillary larger than the others in some species. H:ibits somewhat 

 similar to those of the Diadectidce, but the prey confined to smaller forms. The enlarged 

 incisors were probably used as in the Labidosaurida;, but less effectively, in loosening clinging 

 molluscs or extracting such as were concealed in cracks or burrows. Largely molluscivorous ; 

 not raptorial. 

 Diadectida;. 



Incisor-teeth chisel-shaped; anterior cheek-teeth conical; no caniniform tooth; median cheek-teeth 

 widened transversely with more or less well-developed tubercles on the inner and outer ends, 

 and a median eminence, the apex of which was sharp and elongated transversely to tlie greatest 

 diameter of the tooth. Surface of the cheek-teeth marked by a sculpture of fine radiating 

 lines when first erupted, but the surface soon worn to a flat or oblique surface. .Small conical 

 teetli on the vomer. Molluscivorous; possibly partially herbivorous (durophagous). 

 Bolosaurida; (Bolosaurus and Desmatodon). 



Anterior teeth in Bolosaurus small, conical; cheek-teeth large for the size of the animal, with sharp, 

 elevated outer or inner cusps which i ise above a flat surface at one side of the base. Cheek- 

 teeth of Desmatodon, the only part known, between those of Bolosaurus and Diadectes. Habits 

 indeterminable from the teeth." 

 Pantylosauria. 

 Pantylus. 



Incisors short and blunt; very slightly larger than the cheek-teeth; cheek-teeth short, blunt cones, 

 apex with short, sharp point when fresh; strong, blunt crushing-tcctli set in plates on the maxil- 

 lary and dcntary. Molluscivorous (durophagous, conchifragous). 

 Gymnarthria. 



Gymnarthrus ( Cardioccphalus) . 



Teeth llattencd conical; greatest diameter antero-posterior; increasing in size from before back- 

 ward, the incisors being much smaller than any teeth behind them. No great power of seizing, 

 but seemingly an ability to chew or lacerate, as the most powerful teeth are near the i^osterior 

 of the jaw. Carnivorous; not predaceous. 

 Uncertain in Position. 

 Casea. 



Teeth on the edges of the jaws short, blunt cones, few in number, and decreasing in size from before 

 backward. Palate covered with short, blunt teeth. Williston says that the teeth show con- 

 clusively that it was herbivorous, and perhaps fed on soft, succulent meadow vegetation. 

 This statement is not conclusive. The teeth might have been used for hard animal food. 

 Herbivorous (?) or carnivorous (?); durophagous. 



= Broom (Bull. Am. Mus. Nat. Hist., vol. xxxii, art. xxxii, 1913) has recently reviewed the work of 

 Case upon Bolosaurus, associating parts of the axial skeleton with the skulls, which Case did not feel justi- 

 fied in doing, and has described as new a form, Opiiideirus, which he distinguishes by tlie presence of acces- 

 sory cusps on the side of the large cusp. Williston (,Sc., vol. 38, p. 825, 1913) has referred the bones of the 

 axial skeleton described bv Broom to Arroscelis. 



