227 
SERPULA triangulata. 
TAB. DCVIII. —Jig. 7. 
Spec. Char. Repent, roundish,, elevated., smooth, 
three angles upon the back, the central one 
elevated into a keel ; lines of growth circular. 
A much smaller and more cylindrical shell than the last, 
which it very nearly approaches ; indeed there are upon 
the same mass of Stone several individuals so near S. tri- 
carinata that, except in size, we cannot detect a differ- 
ence. 
Brought from Bradford, Wiltshire. Upon the same 
surface are two other species of Serpula, an Exogyra ? 
and portions of the Pear Encrinite. 
SERPULA runcinata. 
TAB. DCVIII.— -fig. 6. 
Spec. Char. Repent, subtriangular, with three 
distinct serrated or lacerated keels upon its 
back ; aperture round. 
Less than a crow’s quill, tortuose, with an expanded 
base ; the back is round, with a central and two lateral 
keels, the latter are particularly sharp and lacerated. 
Upon an unnamed Plicatula, attached to a mass of 
Coral from the Coral Rag of Shotover Hill : the upper fi- 
gure is magnified. 
