54 S. W. WILLISTON 



as can be made out, are short and small. The first and last plates 

 are larger than the others, the first subcrescentic in outline, the 

 last oval, with its two diameters nearly equal. The carapace is 

 broadest transversely in front, and tapers to the end. The shields 

 are fifteen in number in each specimen, which singularly is the same 

 number as that of Cacops, and probably also that of Dissorophus. 

 Each plate is strongly pitted, like the surface of the skull. They are 

 not at all imbricated, but lie side by side, touching each other in 

 both specimens. • 



APPENDICULAR SKELETON 



So far as the clavicular girdles are visible, they show but little 

 difference from that of Cacops. The interclavicle and clavicle 

 are smooth externally and are of moderate size ; the clavicle has an 

 elongate process for attachment to the scapula. The scapula is for 

 the most part hidden below the carapace; that part which is visible 

 is not unlike the scapula of Cacops. The humerus is stouter than 

 in Cacops", the extremities are less dilated, and the lateral process 

 is not as stout. What appears to be the right ulna and a part of 

 the hand are shown on the same side of the block as that of the 

 carapace. Six, perhaps seven, carpal bones are seen, together with 

 indications of three fingers, the fifth one with the metacarpal and 

 first phalange in place, the fourth and third represented by fragments 

 of the metacarpals only. The hand clearly was short and broad. 



Of the hind extremity, the right femur, tibia, fibula, three tarsals, 

 and two metatarsals are in position. The femur has very prominent 

 adductor crest like that of Cacops, but is distinctly stouter than in 

 that genus. The tarsals are probably the third and fourth distalia 

 and a centrale; and the metatarsals doubtless correspond with the 

 distalia. The feet were evidently more elongate than the hands. 



As regards the species, it is very probable the genus includes that 

 to which I gave the name Aspidosaurus peUatus from the Craddock 

 bone bed. However, inasmuch as there is yet no evidence of a 

 slender inferior process on any of the shields of these specimens, 

 the present species may be provisionally called texensis. 



It gives me great pleasure to name the genus in honor of my 

 friend Dr. Ferdinand Broili, who has contributed much to our 

 knowledge of the American Permian vertebrates. 



