45 
sides in the alternate joints, so that the line of junction in which they overlay 
each other, becomes an acutely angular zigzag, and they are thus, as it were, 
dovetailed together; at the same time they shorten their points, not reaching 
much beyond the middle of the width occupied by the series rising from the 
same arm joints, this shortening continues until the disposition of the parts 
at length produce a regular division, extending in a crenated line through the 
middle of each series, thus giving two joints instead of one to each arm, now 
properly called fingers, and consequently 20 joints to the whole circumference. 
Each of these finger joints is of a semi-horse-shoe shape, and presents 
externally a tubercular convexity towards the points of its dovetailed inser- 
tion. in order to allow greater freedom and ease of motion to the contiguous 
joints. 
Each of the joints sends off laterally a Tenracuium (PL. 11. fig. 2.) formed 
of a series of minute depressed horse-shoe shaped joints, tapering to a point, 
Like the finger joints, the approaching sides of the alternate tentacula are 
insinuated or dove-tailed into each other, whence a sort of double serrated edge 
appears. When the fingers are folded up, in which position the figure of this 
part bears the nearest resemblance to that ofa lily, the tentacula are all folded 
together in the centre, and arranged in an angle with their points upwards, 
thus forming a conical fasciculus. 
Having thus described the appearance and character of the joints, I shall 
proceed to a general survey of the abdominal cavity containing the viscera 
(Pu. 11. fig. 3.) which is formed by the pelvis, coste, and scapule. In this 
species it js not of a funnel-shaped figure as in Apiocrinites, but rather has the 
form of a much depressed urn, being widest where the first coste are provided 
with the lip-like processes, then becoming saucer-shaped, and opening at the bot- 
tom in a pentagonal aperture between the interior truncated points of the 
pelvis conducting into the alimentary canal. There also exist two rows of 
orifices in the cavity, formed by the two series of coste, and the scapule, 
and first arm joints, as noticed when describing Apiocrinites rotundus. If 
we may judge by analogy, and from a representation in Horer’s account of the 
Encrinite, (t. 1x. fig. 13.) we may with considerable probability conjecture that 
this abdominal cavity was also closed by an integument protected by nume- 
rous plates, having in its centre the aperture of the mouth, and spreading 
over the inner cavity of the arms, fingers, and tentacula, similar to that 
