240 



its surface, a very important, and I think, a very decisive, circum- 

 stance, in the structure of this body, was discovered. In the superior 

 part of the processes, of the exterior edges of which the abovemen- 

 tioned ridges are formed, numerous transverse separations exist, at 

 the distances of about the thirty-second part of an inch, which ap- 

 pear to be articulations similar to those which occur between the os- 

 .siculae of the fingers of the lily encrinite, and must have given to 

 these parts of this animal a capacity for similar motions, with those 

 which were performed by the fingers of the lilv encrinus. Consider- 

 ing these parts then, for a moment, as the fingers, let us trace back, as 

 far as we can, and we find, as has been already noticed, that two 

 of these fingers proceed from each of the bodies, in the inferior part 

 of the fossil; which therefore bear, in this respect, a close resem- 

 blance to the arms of the lily encrinite. Besides this we also disco- 

 ver, in those parts of these bodies which form the inferior surface of 

 the fossil, several transverse fissures which may have been the joints, by 

 which the extension and contraction of these bodies might have been 

 admitted. Everything, indeed, in the form and structure of this 

 body, serves to show that, like the lily encrinus, it was capable of 

 being alternately expanded and contracted for the obtaining and the 

 securing of its prey. Whether the digital processes were beset, on 

 their internal part, with articulated tentacula, this specimen will not 

 allow us to discover. 



On various parts of the surrounding matrix are oval impressions, 

 which evidently appear to have derived their figures from the oval ver- 

 tebrae with which the trunk of the animal had been formed. This 

 conjecture receives considerable confirmation from the impression, 

 which is faithfully represented as existing on the matrix by the side 

 of the above-described body : this impression having very much the 

 appearance of being produced by the oval trunk of an encrinus, the 

 vertebrae of which must, however, have materially differed from the 

 oval vertebrae, represented Plate XIII. Fig. 32, 40, 41. 



