55 
joints affected, is exhibited in oneinstance (Pr. 11. fig, 10.) precisely in the same 
manner as was before noticed in the A piocrinites rotundus, 
COLUMNAR FRAGMENTS, smaller and rather neater than those of the species 
just described, occur in the oolite at Dundry, the forest marble at Chippenham, 
and the chalk near Lyme. It remains to be ascertained by the acquisition of per- 
fect specimens, whether these belong to a variety of P. Caput Medusa, or pos- 
sess peculiar characters sufficient to distinguish them as a new species, 
