340 



CEPHALASPIS ASTEROLEPIS (Harley). 

 By J. "\V. Salter, Esq., F.G.S. 



(See the Photograph placed as the Frontispiece to this Volume.) 



An oblique view of a. large specimen, seven inches broad, found on the 

 east side of Skerrid-vawr, by E. Y. Steele, Esq., of Abergavenny, and now in 

 the cabinet of J. E. Lee, Esq., of Caerleon, Monmouthshire. 



The surface is mostly abraded, and the large tubercles of enamel only 

 Been in parts ; but the peculiar form of head, a broad and blunt pointed gothio 

 arch is well preserved in this specimen — the largest known. The eyes are 

 small, placed more than half way from the vertex to the front, twice their own 

 shorter diameter apart, a nai-row depression between them, with a tubercle 

 behind it, and then a broad oblong flat space Ih inches long, by J of an inch 

 broad, appears to have been bounded by low rir'ges of enamel. Posterior to this 

 the vertex rises to a sharp high ridge, more elevated than in any other species, 

 but unfortunately imperfect. We do not know the cervical spine. The lateral 

 cornua (in Dr. M'CulIough's cabinet) sre 3 inches long, measuring from their 

 contracted base, and are both larger, and more cylindrical, and narrower, 

 than in the typical 0. Lyellii. The polygonal vascular areas which cover the 

 head are small in this species. On the under side, the incurved bony margin 

 is broad at the head angles, and as roughly tubercular as on the upper surface. 

 Bound the front it becomes semi-cylindrical. The enamel tubercles appear to 

 have been one on each polygonal area. On the spines they are clear, compressed, 

 and all but shortly spinose. 



The length is 6 inches, including the extreme cervical point, which ia 

 loit in this magnificent specimen. 



