PLATE IX. 



Fig. 1. POTERIOCRINUS CRASSUS. 



1. — lateral view, shewing a large portion of the proboscis, &c. 



Fig. 2. PoTERiocRiNUS ROSTRATUS. «, b, c, d, e,f,g. 

 2, a. — column and auxiliary side arms. — 2, cf. — side arm. 



2, b. — lateral view of a small specimen, exhibiting tlie column, rays, and tentacula. 

 2, c. — small specimen shewing the proboscis. 

 2, d. — proboscis with some of the pointed plates at the apex. 



2, e. — portion of the same enlarged. 



2,/. — lateral view of the body of an adult specimen. 



Fig. 3. P0TER10CRI^■US GRANULOSUS, a, b, c, d, e,f. 



3, a. — lateral view shewing the intermediate plates at the base of the proboscis. 

 3, h — view of the internal cavity, and the ray-bearing articulations. 



3, c. — shewing the columnar articulations on the dorso-central plates. 



3, d. — inverted lateral aspect exhibiting the arrangement of the plates, &c. 



3, e. — dorso-central view, shewing tlie pentapetalous opening into the internal cavity, 



and communicating with tlie columnar canal. 

 3,y. — portion of a column. 



3, g. — part of a column imbedded in the matrix. 



Fig. 4. PoTERIOCRINUS PLICATUS. a, b, c, d, e,f. 



4, a. — lateral view, shewing a portion of the column, &c. 



4, b. — view of the internal cavity, shewing the sinuated edges of the ray-bearing plates, 



as also the ray articulations. 

 4, c. — lateral aspect, exhibiting the arrangement of the plates. 



4, d. — ray-bearing plate, shewing the manner in which the plates articulate at the sutures. 

 4, e. — articulating surface of a ray-bearing plate, shewing the wreath-like crenulations 



around it. 

 4,/. — enlarged view of a portion of the same. 



PLATE X. 



Fig. 1. POTERIOCRINUS EADIATUS. «, b. 



1, a. — lateral view, exhibiting a large portion of the proboscis, bifurcations of the rays, 



and a part of the column. 

 1, 6.— lateral aspect, shewing the arrangement of the plates, and the radiating ridges on 



them. 



