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, arid 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 aTENTACULUM (PL. u. 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 tenlacula 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 of a 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 

 {PL. u. fig. 3) which is formed by the pelvis, costae, and scapulas. In this 

 species it is not of a funnel-shaped figure as in Apiocrinites, but rather has the 

 form of a much depressed urn, being widest where the first costse 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 costas, and the scapula, 

 and first arm joints, as noticed when describing Apiocrinites rotundus. If 

 we may judge by analogy, and from a representation in HOFER'S account of the 

 Encrinite, (t. ix. 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 



