7 
TRIGONIA nodosa. 
TAB. DVII.— -^g*. 1. 
Spec. Char. Obovate, depressed ; anterior part 
covered with rows of large knobs., a portion of 
the posterior part plain ; superior edge straight. 
A large rather depressed species : two or three rows 
of slightly elevated tubercles extend from the beaks to- 
wards the posterior margin, which is truncated irregu- 
larly : from that row of tubercles which passes over the 
disk, 8 or 10 others extend obliquely over the whole of 
the anterior portion. Much resembling T. daedalea 
(M. C. 88.) ; but it is larger, and the tubercles are less 
numerous, and do not cover the posterior portion. Casts 
of the insides have been preserved in Mr. Sowerby’s 
Museum since 1815 s they were found in the Green-sand 
at Hythe in Kent. 
