EXTENT OF CRINOIDEANS. 323 



him, through his highly philosophical analysis of the struc- 

 ture of this curious family of fossil animals.* 



From the details I have thus selected from the best autho- 

 rities, with a view to illustrate the most important parts that 

 enter into the organization of the family of Encrinites, it is 

 obvious that similar investigations might be carried to an al- 

 most endless extent by examining the peculiarities of each 

 part throughout their numerous species. We may judge of 



* Our PI. 47 gives Mr. Miller's restoration of two other genera, fig. 1, 

 the Apiocrinites rotundus, or Pear Encrinite, with its root or base of attach- 

 ment, and its arms expanded. Fig. 2 is the same with its arms contracted. 

 Two young individuals and the broken stumps of two other small speci- 

 mens, are seen fixed by their base to the root of the larger specimens, show- 

 ing the manner in which these roots are found attached to the upper surface 

 of the great oolite at Bradford near Bath. When living, their roots were 

 confluent, and formed a thin pavement at this place over the bottom of the 

 sea, from which their stems and branches rose into a thick submarine forest, 

 composed of these beautiful Zoophytes. The stems and bodies are occa- 

 sionally found united, as in their living state ; the arms and fingers have 

 almost always been separated, but their dislocated fragments still remain, 

 covering the pavement of roots that overspreads the surface of the subjacent 

 Oolitic limestone rock. 



This bed of beautiful remains has been buried by a thick stratum of clay. 

 Fig. 3 represents the exterior of the body, and the upper columnar joints of 

 this animal, about two-thirds of the natural size. Fig. 4 is a longitudinal 

 section of the same, showing the cavity for the viscera, and also the large 

 open spaces for the reception of nourishment between the uppermost en- 

 larged joints of the column. 



At fig. 5 we have the Actinocrinites 30-dactylus, from the corboniferous 

 limestone near Bristol. D. represents the auxiliary side-arms which are 

 attached to the column of this species, and B its base and fibres of attach- 

 ment. Fig. 6 represents its body, from which the fingers are removed, 

 showing the pectoral plates, Q, and capital plates, R, which form an in- 

 tegument over the abdominal cavity of the body, and terminate in a 

 mouth (x,) capable of being protruded into an elongated proboscis by the 

 contraction of its plated integument. Fig. 7 represents the body of an 

 Encrinite in the British Museum, figured by Parkinson, vol. 2, fol. 17, 

 fig. 3, by the name of Nave Encrinite. The mouth of this specimen 

 also is seen at X, and between the mouth and the bases of the arms, the 

 series of plates which form the upper and exterior integuments of the 

 stomach. 



