PLATE XXVIII. 
Pecren (continued). 
P. (Camptonectes) cinctus, Sow. Claxby Ironstone (zone of B. lateralis) 
of Claxby. Woodwardian Museum. (P. 152.) 
Fies. 
la. Right valve x 4. 14, portion of the same, natural size. 
2a. Left valve of another specimen X 2. 2, portion of the same, natural size. 
3. Portion of left valve with the concentric laminz well preserved X 2 
(The ears in figs. 1a, 2a, have been partly completed from other specimens.) 
