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. Iwvis 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. tuberculatum — 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. 



BLASTOID^. 



Gen. PENTREMITES. — Pelvis of three unequal pieces, 

 two pentagonal and one tetragonal ; scapulae large, cmar- 

 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 subglobular ; pelvis saucer-shaped, convex; sutures 



with parallel impressed lines. — {Say, Journ. Acad. Phil, iv.) Zool. Journ. 

 ii. 314 — Near Bath. 



2. P. Derbiensis Body subglobular ; pelvis small, pentagonal, and con- 

 cave ; surface granulated. — Sower. Zool. Journ. ii. S17.— Carboniferous Lime- 

 stone, Derbyshire. 



3. P. elliptica Body elliptical, jjclvis small, pentagonal, and concave; 



granulated.— A'ou>e»-. Zool. Journ. ii. 318. — Near Preston, Lancashire. 



