184 
PALAEONTOLOGY OF NEW-YORK. 
CrENUS CORONOGBUHTS (n.g.). 
[ Gr. xopuvri, corona; xpivog, lilium.] 
Body very broad, liemisplierical ? towards the upper margins composed 
of numerous plates. 
Arms numerous, proceeding from the upper margin of the body: summit 
flat, composed of numerous small plates. 
Column and base unknown. 
Coronocrinns polydactylus (n. s.). 
Plate YI. Fig. 4-6. 
Base unknown : upper part of body, near the base of arms, composed 
of numerous small plates. Summit nearly flat, composed of numerous 
minute hexagonal plates. 
Arms numerous (about forty), consisting of a double series of plates, which 
are wedgeform and closely interlocking at their inner edges, and rising 
abruptly from the same line at the upper margin of the body. 
Proboscis unknown. 
The specimen from which the genus and species are described is a portion of the 
circumference of the body, which has originally been nearly three inches in diameter 
on the crown. The arms proceed abruptly from the upper margin of the body. The 
summit is slightly depressed just within the arms, and'thence towards the centre 
is slightly convex. The fragment preserves the bases of eleven arms; and as it is 
scarcely more than a fourth of the circumference, we may infer that there were 
forty arms on the entire individual. The construction of the body as far as seen, 
with the mode of origin of the arms, the character of the summit, etc., are sufficient 
to indicate the form as a distinct generic type. 
Fig. 4. Lateral view of a fragment of the upper part of the body and bases of the arms. 
Fig. 5. View of the summit, showing its structure, and the origin of the arms. 
Fig. 6. Enlargement of some plates of the summit. 
Geological position and locality. In the shaly limestone of the Lower Helderberg 
group, Schoharie. 
