14 



b Fingers formed of two series of joint*. II. GEN. ENCRINITF.S. 



* Column round. 



o Alimentary canal round. 1 Sp. moniliformi*. 





H. DIYMION. SEMIARTICULATA. Plate-like joints form- 

 ing the superior cup-like body of the animal, arti- 

 culating imperfectly to each other. 

 A Pelvis formed -of. iive joints 



Mvtt* 



9 Supporting five costal plates, 

 a Column not enlarging. 



a Fingers formed of a single series of Joints. 

 * Column round, 

 o Alimentary canal round. 



Articulating surface of columnar joints 



radiated, 

 t Auxiliary side arms round. 



J Auxiliary side arms placed irregular. IV. GKN. POTERIOCBINITES. 



1 Joints of fingers thick. 1 Sp. crassus. 



2 Joints of fingers slendec. 2 Sp. tenuis. 



III. Division. INARTICULATA. Plates forming the su- 

 perior cup-like body of ihe animal, adhering by 

 sutures, lined by muscular integument. 



N. B. In a young state PBTERIOCRIN ITES TEN vis may be erroneously 

 considered ai belonging to tins family,, on account of the 

 undeveloped state of the articulations, 



A Pelvis formed of five plates, 

 a Supporting five costal plates. 

 a- Column not enlarged. 



a Fingers formed of a single series of joints. 

 * Column round 

 o Alimentary canal round. 



Articulating surface df columnar joints ra- 

 diated. 



't Auxiliary side arms round. 

 .J Auxiliary side arms placed irregular. VI. GEN. CTATHOCKINITES. 



