PLATE XV. 

 Fig. 1. Pentacrinus Johnsonii. (Auslin.J a, to c. 



1 a — lateral aspect of a well preserved specimen selected from a group of the P. 



Johiisoiiil, which lie embedded in various positions on the surface of the stone 



slab, together with numerous portions of columns. 



'J'he rays, tentacula, column, and claspers are all clearly exhibited in 

 this figure, as well as the Ophiura lying across the column and among the rays. 

 1 b — lateral aspect of another individual drawn from the same group. In this figure 



the rays are not quite so much expanded as in the preceding one. 

 1 c — portion of a column with the delicate claspers attached to it, shewing the manner 



in which they are arranged in circles of five. 



Fig. 2. Pentacrinus tuberculatus. (Miller.) a, toe. 



2 a — portions of the rays and tentacula. 



2 b — part of a column with a side arm attached. 



2 c — upper portion of a column with the enlarged columnar joint at its summit, and 



which probably subserves the purpose of the dorso-central plate. Portions 



of the body and lower rays are also seen in this figure. 



The specimens from which figures 2 a, and 2 c are drawn form part of 

 the collection in the Bristol Philosophical Institution. 



PLATE XVI. 



Fig. 1. Pentacrinus Millerii. a, to /. 



1 a — lateml view of a specimen which exhibits the lower part of the rays and tentacula 



as also a portion of the column and clasper.". 

 1 J — dorso-central aspect which shews some of the fine terminal rays, tentacula, &c. 

 J c — dorso-central view of a different specimen. 

 \ cl — portion of a column with the delicate claspers attached. 

 \ e — part of a column with the articulating surface of a columnar joint. 

 1 ^'—portion of a ray with the jointed tentacula. 



