204 



of which is pierced by a foramen. These foramina, as may be seen 

 on the flat surface of the uppermost vertebrae of this specimen, reach 

 to, and unite with, the central circular foramen. Each of the verte- 

 brae being thus beset with these projections, the trunk is thereby 

 rendered very rugged ; and still more so, as the vertebrae approach to- 

 wards the ramose termination, where the projecting processes gradu- 

 ally acquire an increase of length. On acquiring about a quarter of 

 an inch in length, these processes separate into ramifications, and con- 

 tinue thus to ramify, at the distance of a quarter, or of half an inch, 

 until they form a brush -like mass, as is above represented. 



It was observed, when speaking of the lily encrinite, that the crenu- 

 lated articulation was obliterated, or nearly so, in those parts which 

 appeared to have performed the office of pedicles to the animal. A 

 similar circumstance is observable here; for among the ramifications 

 above described, there are several in which traces of the almost ob- 

 literated crenulated articulations may be perceived : and where the 

 internal part of these bodies is exposed, as may be seen in the figure, 

 they are found to be hollow, and manifesting similar traces of the 

 original crenulated articulations. 



When the similarity of the vertebrae in this specimen, and in that 

 mass in which the skeleton of the body part of the animal is imbed- 

 ded, is considered, little doubt can exist as to their both being parts 

 of the same species : and when the form and construction of the ra- 

 mose parts of this specimen, so well adapted for performing the of- 

 fice of pedicles, are contemplated, as little hesitation can occur in 

 admitting, that these parts constituted the inferior termination, the or- 

 gan of attachment, of this species of the encrinus. 



Having, I trust, established the existence of this peculiar species, 

 I shall call your attention to the peculiarities observable in its verte- 

 bral trunk. 



The specimen, Plate XV. Fig. 4, which is formed ofaspathose sub- 

 stance, with a reddish tinge, is particularly interesting from its differ- 



