13 
Systematic Arrangement of the Crinotdea, 
* The Etymology of the names adopted will be found in the description of each genus and speeies. 
I. Division. Articuzata. Joints forming the supe- 
rior cup-like body of the animal articulating to 
each other. 
A Pelvis formed of five joints. 
@ Supporting five costal joints. 
a Column enlarging at the summit. 
a Fingers formed of a single series of joints. I. Gen. APtocriniTEs. 
* Column round 
o Alimentary canal round. 
§ Articulating surfaceof columnar joints radiated. 1 Sp. rotundus. 
** Column elliptic. 
o Alimentary canal round. 
§§ Articulating surface of columnar joints trans- 
versely ridged. 2 Sp. ellipticus. 
b Column not enlarging at the summit. 
a Fingers formed of a single series of joints. 
*+* Column pentangular. 
o Alimentary canal round. 
§§§ Articulating surface of columnar joints petal- 
shaped. III Gen. PENTACRINITES. 
+ Auxiliary side arms round. 
t In single series. 
|| Column smooth. 
1 Columnar joints generally alternately 
smaller and larger. 1 Sp. Caput Meduse. 
2 Columnar joints generally of more 
uniform thickness. 4 Sp. Basaltiformis. 
{| Column tuberculated, 5 Sp. tuberculatus. 
t{} Auxiliary side arms in double series. 
{| Column smooth. 3 Sp. subangularis. 
++ Auxiliary side arms angular. 
} Auxiliary side arms in single series, 
{| Column smooth. 2 Sp. Briareue. 
