278 S. AV. WILLISTON— NEW GENERA OF PERMIAN VERTEBRATES 



Genus Dissorophus Cope. — Dermal carapace extending the fnll width 

 of the body, with a broad and elongated shield in front covering several 

 vertebrae. Cleithrum less expanded and thicker. Scapula much ex- 

 panded antero-posteriorly below. D. multicinctus (articulatus) Cope. 



Genus Cacops Williston. — Dermal carapace but little wider than the 

 vertebrae, narrowed in front and not fused into an anterior shield. Clei- 

 thrum thin and more expanded. Scapula less expanded below, the inter- 

 clavicles and clavicles more slender. C. aspidephorus Will. 



TREMATOPSID^— FAMILY NEW 



It is very evident that the characters of Trematops as given by me^^ 

 are of more than generic importance. The genus represents a distinct 

 family, which may be defined as follows: 



A median foramen back of premaxillse; large antorbital vacuities. 

 Otic notch wholly enclosed by bone, the opening small and extending far 

 forward. Palate with two pairs of large teeth back of the nares and a 

 single one on each vomer. No parasphenoid. Eibs short, the anterior 

 ones expanded distally. Twenty-two or twenty-three presacral vertebrae; 

 a single sacral; tail short. No dermal armor or carapace. Cleithrum 

 unknown. Clavicles and interclavicle small, without dermal pittings. 

 Humerus with ectepicondylar process. T. milleri Will. 



Restoration 

 (Plate 17) 



The figures of Cacops aspidephorus given in the following plates and 

 the mounted skeleton of plate 17 are nearly all from a single specimen, 

 found with all of its parts intact and closely related in the matrix, lying in 

 a prone condition. It was lying near the right side of one of the blocks of 

 clay, taken up with the aid of bandages, and in separating the blocks 

 some fragments of the right limbs were probably lost; the remainder 

 probably are yet lying in the adjacent block, but the time required to 

 work out each of these separate blocks, with their numerous skeletons 

 and parts of skeletons, has rendered it inadvisable to wait till the whole 

 material has been prepared before publishing, especially as but very little 

 new information is to be gained. Inasmuch as the other skeletons ex- 

 humed are of a slightly larger or smaller size, their bones have not been 

 used to replace the tibia and fibula, radius and ulna, and feet of the right 

 side, which have been modeled in plaster from the left side. Numerous 



1^ Journal of Geology, July-August, 1909, p. 389. 



