$I —, 
720 THE CRINOIDEA CAMERATA OF NORTH AMERICA. 
Remarks. — This genus bears the same relation to Platycrinus that Stega- | 
nocrinus does to Actinocrinus. In both groups the rays branch in their free | 
state; but while in Platycrinus and Actinocrinus the covering plates are | 
movable from the costals up, they are in sutural contact in Hucladocrinus and 
Steganocrinus to the end of the appendages, and the latter practically form , 
extensions of the calyx. 
In Part I. of the Revision we placed under this genus only those species 
| in which the arm trunks.extend to the full height of the crown, and in which 
the arms are given off singly from opposite sides. This excluded such 
forms as “ Piatycrinus” preenuntius and “ Platycrinus”’ tuberosus, which have 
unquestionably the characteristics of Hucladocrinus, but less completely ‘ | 
LT ee 
SS eae EA ne 
a ee 
24 TD = 
ay ‘ie 
Sa Se = 
SS 
eH 
developed. 
SSS 
a 
LE | Eucladocrinus millebrachiatus W. and Sp. 
Hy Lj | 
aaa Plate LXXILL. Fig. 1, and Plate LX XIV. Figs. 2, 3, 4, 5,6, 7,8, 9. 
ee | Acad. Nat. Sci. Phila., p. 251). 
1878. W. and Sp.; Proceed. Acad. Nat. Sci. Phila., p. 245, and 1881, Revision, Part II., p. 77 (Proceed. , | 
| | | A rather large species, resembling Platycrinus glyptus in the form of the | 
| calyx and style of ornamentation. Dorsal cup bell-shaped, a little higher 
lia than wide, the rays extended outward and forming above the distichals ten 
| ponderous tubular appendages, two to the ray, which, curving downward, 
re | expose the ventral surface, and give off simple arms to nearly the full height 
of the crown. Ventral disk very short and flattened on the top. Surface 
St 
Hy if of basals and radials marked by rows of small nodes and rugose ridges, | 
E | arranged parallel to the margins of the plates, and radiating to their angles. 
f | Basals forming a saucer-shaped dish, equal in height to one third the 
| | | a length of the dorsal cup, truncated at the bottom, the middle portions de- 
alt | | pressed to the width of the column; the interbasal sutures invisible. Radials 
mice longer than wide, very slightly increasing in width upward, a little gibbous | 
| [r t | in the middle, and swelling toward the facets; the edges of the plates not | 
P| beveled, and the interradial suture lines ill-defined. Facets large, semi- 
circular, facing almost horizontally outward, occupying two thirds the width 
Ti | of the plates and nearly one third their height; the surface slightly pitted 
Wee le in the middle. Costals very short but wide, filling the entire surface of the 
facets, and abutting against the lower end of the interradial plates; the 
distal faces, although the plates are axillary, almost parallel with the proxi- | 
