730 THE CRINOIDEA CAMERATA OF NORTH AMERICA. 
MARSUPIOCRINUS Putt. 
(Not Marsupicrinites BLAINVILLE = Marsupites Mant., nor Marsupiocrinites Watu = Lyriocrinus). 
1839. Puitures apud Murcutson; Silur. System, p. 672. 
1842. Austin; Ann. and Mag. Nat. Hist., Vol. X., p. 109. 
ie57/- Picrur; Traite de Paleont., Vol. 1V., p. 3382. 
1860. Dusarpin and Hurt; Hist. naturelle des Zoophytes, p. 149. 
1878. Anegetin; Icon. Crinoid. Suec., p. 2. 
1879. Zirte.; Handb. der Paleont., Vol. I., p. 365. 
1881. W. and Sp.; Revision, Part II., p. 62 (Proceed. Acad. Nat. Sci. Phila. p. 236). 
1890. §. A. Minter; North Amer. Geol. and Palzont., p. 260. 
Syn. Platycrinus Gn part) — F. Rozmer, 1860; Silur. Fauna West. Tenn., p. 35. 
Syn. Cupellecrinus —Troost; 1850, List Crin. Tenn., p. 61; described by Shum. 1866; Cat. 
Paleoz. Fossils (Trans. St. Louis Acad. Sci., Vol. II., p. 361). 
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Closely related to Platycrinus, but the lower brachials and the first plate 
of the interradial series entering rather more into the dorsal cup; the radial 
facets, instead of being excavated, are nearly straight; the column circular 
instead of elliptic ; and the axial canal very much larger and pentagonal. 
Basals arranged as in Platycrinus, and similarly anchylosed.  Radials 
large, hexagonal in outline; the upper face supports not only the costals 
but also the distichals ; it is straight, or slightly indented for the reception of 
each plate. Costals one, very small and trigonal. Distichals one when there 
is another bifurcation above; they are small, resting with their lower faces 
upon the radials, with one of their lateral faces against a large interbrachial ‘ie 
plate, and at the opposite side against the adjoining distichal of the same 
ray. Arms from two to four to the ray, rather stout and biserial; the 
pinnules large. Ventral disk hemispheric; the orals rather small, pushed 
anteriorly, and quite asymmetrically arranged. The ambulacral plates con- 
sist of regular rows of covering pieces, which branch upon the disk, and are 
| separated trom those of adjoining rays by rather large interambulacral plates, 
ie and the branches from one another by one or two interaxillaries. Column 
| le | of uniform size throughout, and, so far as observed, without cirri, except 
r { i | perhaps at the extreme end. The joints circular, each pair of nodal joints 
iF Tt | enclosing an internodal; the axial canal moderately large and pentagonal. 
z)) tS » Distribution. —The genus occurs in Europe as well as America, and is 
ii | | restricted to the upper Silurian. 
J | Type of the genus: Marsupiocrinus celatus Phill. 
if | | Remarks. — Among his list of the Crinoidea of Tennessee, Troost gives 
| if | under Cupellecrinus the following species: Cupellecrinus Buchi, C. corrugatus, 
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