Page:Geology and Mineralogy considered with reference to Natural Theology, 1837, volume 1.djvu/327

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EXTENT OF CRINODEANS.
323

him, through his highly philosophical analysis of the structure of this curious family of fossil animals.[1]

From the details I have thus selected from the best authorities, 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 almost endless extent by examining the peculiarities of each part throughout their numerous species. We may judge of

  1. Our Pl. 47 gives Mr. Miller's restoration of two other genera; fig 1, the Apiocrinites rotundus, or Pear Encrinite, with its root or base of attachment, and its arms expanded. Fig. 2 is the same with its arms contracted. Two young individuals and the broken stumps of two other small specimens, are seen fixed by their base to the root of the larger specimens, showing 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 occasionally. 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 9. 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 enlarged joints of the column.

    At fig. 5 we have the Actinocrinites 30~dactylus, from the carboniferous 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 attachment. Fig. 6 represents its body, from which the fingers are removed, showing the pectoral plates, Q, and capital plates, R, which form an integument 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.