496 
RADIATA. BLASTOIDiE. Platycrinites. 
Gen. PLATYCRINITES. — Pelvis of three plates; costal or 
intercostal plates wanting the five scapulae ; fingers of two 
series of joints ; column not enlarging near the summit ; 
auxiliary arms round, irregular. 
1. P. l(Bms — Column elliptic ; canal round ; articulating surfaces trans- 
versely ridged ; the five scapulae smooth, having each four fingers. — Mill. Crin. 
74. — Carboniferous Limestone* 
2. P. rugosus. — Column elliptic ; canal round ; articulating surfaces trans- 
versely ridged ; the five scapulae rugose, having each six fingers. — Mill. Crin. 
79 * — Mountain Limestone. 
3. P. pentangularis — Column and canal pentangular ; articulating surfaces 
radiated ; the five scapulae smooth — Mill. Crin. 83 Mountain Limestone. 
4. P. tuherculatus — Column not known ; the five scapulae tuberculated. 
Mill. Crin. 81. — Mountain Limestone. 
5. P. granulatus — Column not known ; the five scapulae granulated — Mill. 
Crin. 82. — Mountain Limestone. 
6. P. striatus. — Column not known ; the five scapulae striated — Mill. Crin. 
82. — Carboniferous Limestone. 
ELASTOID.^. 
Gen. PENTREMITES. — Pelvis of three unequal pieces, 
two pentagonal and one tetragonal ; scapulas large, emar- 
ginate ; five avenues of pores ; column cylindrical, perfo- 
rated, the segments articulating by radiated surfaces ; cy- 
lindrical auxiliary arms at irregular distances. 
1 . V.globosa — Body subglohular; pelvis saucer-shaped, convex; sutures 
with parallel impressed lines. — {Say., Journ. Acad. Phil, iv.) Zool. Journ. 
ii. 314.—Near Bath. 
2. P. Derbiensis — Body subglohular ; pelvis small, pentagonal, and con- 
cave ; surface granulated. — Sower. Zool. Journ. ii. 317 * — Carboniferous Lime- 
stmey Derbyshire. 
3. P. elliptica — Body elliptical, pelvis small, pentagonal, and concave; 
granulated.— Aower. Zool. Journ. ii. 318.-rNear Preston, Lancashire. 
