5i8 FRANK SPRINGER 



ii. Anals numerous, in more than one series. 

 Arms more or less divergent. 

 Primibachs 2. 



RA more or less between BB. 

 Arms dichotomous; iBr numerous . Sagenocrinus 

 2. Anal X and smaller plates occupying only lower part of 

 anal area. 



i. Anals in more than one series. 

 Arms more or less divergent. 

 Primibrachs 2. 

 RA under r. post. R., above line of BB. 

 Arm dichotomous; iBr few . . . Temnocrinus 

 b. No radianal. 



1. Anal X and smaller plates occupying lower part of anal 

 area. 



i. Anals few, mostly confined to single series. 

 Arms more or less divergent. 

 Primibrachs 2. 



Arms dichotomous. 



IBr areas wide; IBr not filling distal face 



ofRR 



Arms heterotomous. 



10 main arm-trunks with ramules inside 

 dichotom; IBr few .... Dactylocrinus 

 Arms more or less contiguous. 

 Primibrachs 2. 



Arms dichotomous; \Er numtroyx?, {n. g.) Amphicrimis 

 Primibrachs 3. 



Arms dichotomous; iBr few . . . Euryocrinus 



2. Anal area filled by solid plates, forming part of calyx wall. 



Anals numerous, in more than one series. 

 Arms more or less divergent. 

 Primibrachs 3 (exceptionally 2). 

 Arms heterotomous. 



10 main arm-trunks with ramules inside 

 dichotom. 

 iBr numerous . . . . . . Lithocrimis 



Arms dichotomous 



iBr numerous Forbesiocrinus 



c. No anals nor radianal. 



Arms more or less divergent. 



Arms heterotomous. Primibrachs, 2. 

 10 main arm-trunks with ram- 

 ules inside dichotom 



