ECHINODERMATA. 143 
genus Jsis, confounding the fossil Hnerinus and the Pentacrinus 
caput Meduse of the existing creation under the name of Jsis 
Asteria. This singular union of an Echinoderm with a genus of 
Polyps had doubtless an influence upon the later, arrangement of 
Lamarck, who placed Hnerinus (see above, p. 80) amongst the sea- 
feathers. ScCHWEIGGER and CuviER restored it to the proper place, 
already assigned to it in the middle of the previous century by 
GuETTARD, who first described Pentacrinus caput Medusa. This 
whole family belongs rather to the former period of the history of 
our globe, than to the present. The species now living in our seas 
are almost all non-pediculate, whilst geological investigation has made 
us acquainted with numerous forms of pediculate sea-lilies. What is 
now a youthful mutable form of life was then the prevalent and 
permanent. The same thing may be observed in other classes also 
with respect to the fossil representatives of genera that are living 
at the present time. 
The chief work on this family is: 
J.S. Minter, Natural History of the Crinoidea, Bristol, 1821, 4to.' 
A. Crinoids affixed. 
a) Sessile. 
Holopus D’OrpiGNY. Calyx affixed, hollow, undivided, with 
scattered tubercles. Four calcareous pentagonal parts at the upper 
margin of the calyx, sustaining four pairs of articulate and pinnate 
arms. 
Sp. Holopus Rangii, D’ORBIGNY, GUERIN Magasin de Zool. 1837, Cl.x. Pl. 3; 
from the Caribbean Sea at Martinique. Both in the want of a stem and 
the number of the arms this genus differs from the other Crinoids. 
b) Pediculata. An articulate column sustaining the calyx, 
* Tesselata. Calyx non-articulate. 
a) Rays or arms none. 
‘ 
Genera: Spheronites HistncEr, Pentatrematites Say (Pentremites 
Goupr.), Lchinospherites WAHL., Hemicosmites GRAY, Sycocystites 
v. Bucs. 
Fossil genera from the Transition- and Mountain-limestone. Comp. Bronn, 
Letheea geognostica 1835, Tab. IV. fig. 1, &e. According to the opinion of 
some these were pediculate Zchint. 
f) With rays. 
* See also W. Bucknann, Geology and Mineralogy, London, 1835, pp. 416—442, 
