1896.] 143 [Cope. 



3Ieasureinents. mm. 



Width of occipital condyles 150 



' ' foramen magnum 65 



' ' sagittal crest 17 



" anterior border of nasal bones 90 



" skull at sagittal crest 170 



" sphenoid at middle of for. lacerum 135 



Anteroposterior diameter of glenoid surface 115 



Length of nasal canal 350 



" from occipital condyles to anterior nares 450 



" " foramen magnum to posterior end of sag- 

 ittal crest (oblique) 210 



Length of sagittal crest 15 



" from " to anterior nares 195 



This specimen was obtained hj Prof. Arthur Bibbins from a Miocene 

 marl from near the mouth of the Potomac river, in Maryland. I am 

 under much obligation to the Rev. John T. Goucher, President of the 

 Woman's College, of Baltimore, for the opportunity of studying the 

 specimen, which belongs to that institution. 



Cephalotropis coronatus, gen. et sp. nov. 



Char. gen. — Parietal bone separating supraoccipital and frontal by a 

 considerable space and presenting a sagittal crest. Frontal extensively 

 overlapped by the maxillaries, premaxillaries and nasals. Nasals elon- 

 gate, distinct from the adjacent elements. Frontal presenting divergent 

 temporal angles. 



This genus differs from Cetotherium in the presence of temporal 

 ridges or angles. It difters from Metopocetus in the free elongate nasal 

 bones. 



Char, specif. — The specimen M'hich 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 Metopocetus durinasus and Cetotherium 

 megalophysutn, 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 tri 

 angular 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 



