BATOCRINIDAD W. and Sp. 
MonocyLic. THE LOWER BRACHIALS WITH WELL DEFINED INTERBRACHIALS BETWEEN THEM 
FORMING AN IMPORTANT PART OF THE DORSAL CUP. RADIALS IN CONTACT EXCEPT 
AT THE POSTERIOR SIDE, WHERE THEY ARE SEPARATED BY A HEPTAGONAL ANAL PLATE, 
WHICH IS FOLLOWED BY A SECOND ANAL BETWEEN TWO INTERBRACHIALS. 
Analysis of the Genera. 
I. 
VENTRAL DISK HIGHLY DIFFERENTIATED: THE PLATES LARGE AND 
HEAVY, FORMING A RIGID INTEGUMENT. ARMS NOT BRANCH- 
ENG: BEYOND, BRU OA Xm) e t.7, qepeeice: = ee nee eee emer BATOCRINITES. 
A. ARMS BISERIAL; BASALS THREE. e 
1. ANUS AT THE END OF A TUBE. 
a. Interbrachials separated from interambulacrals by 
an arch of brachials. 
Calyx biturbinate. 
Arms short, equidistant; anal tube very 
long and central; respiratory pores 
(Meee SOUT SF oe Batocrinus. 
Arms long, paddle-shaped; anal tube excen- 
tric; respiratory pores twenty .. . Hretmoerinus 
Calyx conical, dorsal cup almost flat, ventral 
disk greatly predominating in height; 
anal tube central ; respiratory pores 
twenty 55 os a ew ee Oprosaliocnonas: 
b. Interbrachials connected with interambulacrals. 
Arms arranged in groups, the openings di- 
rected upward; anal tube large, central. 
Calyx pyriform to wheel-shaped ; arms 
twenty ; respiratory pores not visible . Lobocrinus. 
Calyx elongate, biturbinate or subovoid ; 
arms twelve to sixteen ; respiratory pores i 
2) aria te eee ele ae Bs eee ag Macrocrinus. 7 
ec. Interbrachials in contact with interambulacrals at 
anal side only. 
Calyx wheel-shaped; anal tube very large, 
central; arms short, single or paired; re- 
Spirabory Pores uwelby ~ we i eee Hutrochocrinus. i 
46 
