MARYLAND GEOLOGICAL SURVEY 39 



divergent temporal angles .... differ from Metopocetiis in the free 

 elongate nasal bones." Cope, 1896. 



Cephalotropis coroxatus Cope. 



Plate XIX, Fig. 1. 



Cephalotropis r.oronatus Cope, 1896, Proc. Amer. Philos. Soc, voL xxxv, No. 151, 

 p. 143, pi. xi, fig. 2. 



Description. — " The specimen -which represents this species is a portion 

 of the cranium which includes the elements which surround the brain 

 except the occipital, the superior part of the latter remaining; together 

 with the posterior parts of the maxillaries, premaxillaries and the 

 greater part of the nasals, and the basisphenoid and presphenoid in part, 

 and a considerable portion of the left temporal. The sutures distin- 

 guishing the several elements are distinct, so that the boundaries of 

 the latter can be readily distinguished. In describing this fragment I 

 will compare it especially with the Metopocetiis durinasus and Ceto- 

 therium megalophysum, where the corresponding parts are preserved. 



" The supraoccipital angle is produced further anteriorly than in either 

 of the species named, and the sagittal crest is longer than in either. 

 The summit of the smooth occipital surface forms a transverse border, 

 which cuts off the apex of the occiput, thus bounding posteriorly a 

 triangular area, of which the sides are a little longer than the base. 

 This triangle has a low, median keel, on each side of which the surface 

 is; concave, and is marked with numerous irregular fossae. The surface 

 has been evidently the seat of the insertion of something; but whether 

 it was entirely of a ligamentous character or whether some tegumen- 

 tary structure had its basis there I do not know. The superior border 

 of the temporal fossa is regularly concave towards the middle line, and 

 regarding the sagittal crest as restricted to the parietal bone, its trun- 

 cate edge is wider at the extremities than at the middle. The nar- 

 rowest portion of the crest is nearer the frontoparietal than the parieto- 

 occipital suture. The temporal ridge is in regular continuation of the 

 edge of the sagittal crest, and becomes transverse in direction towards 

 the orbital border of the frontal bone. This border is broken off. 



