31 
P. Srriata.’ Lin. 111). D. p. 37.—Don. t. 117.— 
Mont. 26.—Turt. B. 11.—P. Cuavara. Lam. 9.— 
Po Namuss ult. 27.-Wood,.G.C. t.16) f. 1, 2,185 
4,8.—Ch. f. 867, 8,9.—Reeve. t. 24. f. 2.—Sow. G. 
J. 2.— Transverse, conoid, posteriorly short, tumid and 
rounded, anteriorly produced and  subcompressed ; 
posterior area strongly reticulated by arched strie, 
elsewhere slightly striated except a smooth triangular 
space at the posterior ventral margin; one large 
rounded accessary plate over the hinge before which is 
a lengthened one a third connects the ventral edges ; 
apophysis long slender and curved. 2...1. Ship's 
timber. 
* * Valves not divided by a groove. 
P. Dactytus. Lin. 1110.—D. p. 35.—Lam. 1.— 
Mont. 20.—Turt. B. 8.—Ch. f. 859.—-Don. t. 118. 
—Sow. G.—Reeve. 24. f. 1.—F. 457.—Transversely 
elongated, beaked posteriorly and rounded anteriorly ; 
with concentric waved muricated ridges and indistinct 
radiating striz towards the beaks; hinge margin re- 
flected and supported by numerous small plates so as 
to form quadrangular cells; four accessary plates. 4 or 
5. Common. 
P. Canpipa. Jan. 1111.—Don. t 132.— Mont. 24. 
—Turt. B. 10.—D. p,36.—F’. p,457,—Lam. 3.— Ch. 
