iba] 
TRIBE PHOLADARIA. 
TRIBE PHOLADARIA. 
Devoid of a tubular sheath: valves with accessory pieces or 
considerably yaping posteriorly. 
PHOLAS. 
Shell bivalve, equivalve, transverse, gaping at both extremities, with 
various accessory pieces either on the hinge or below it ; inferior 
margin of the valves inflected. 
* Valves not divided by a radiating groove. 
P. Dacryius.* Lin. 1110.—D.p. 35.— Ch.f. 859.— E. t. 168. 
f. 2,3,4.—Lam. 1.-—Don. t. 118.—B. t. 1. f:7.—Son. G.— 
Reeve. t. 24. f. 1.—Wood. G. C. t. 13.— Turt. B. p. 8.— Mont. 
p. 20.—W.t. 2. f. 1. Elongated-oblong, beaked at one end and 
rounded at the other, with concentric waved muricated ridges and 
indistinct radiating strie towards the beaks; margin above the 
umbones reflected, circular and supported by numerous small plates 
so as to form quadrangular cells: 4 accessory plates. 4 or 5. 
— Hurope.? 
P. OrteNTALIS. Gmel. 3216.—D. p. 36.—Lam. 2.—Ch. f. 
860 —W.t. 2. f. 2. Elongated-oblong, white, brittle, and nearly 
closed at one end, one half of each valve smooth and the other 
marked with reticulated striz ; margin straight. 13 .. 6.—Siam and 
Tranquebar. Somewhat resembles the last but 7s not beaked. 
P. Canprpa.* Lin. 1111.—D. p. 36.—Lam. 3.—W. 1. 2. f.3. 
Don. t. 132.—Ch. f. 861, 2.— Wood. G. C.t. 14. f.3, 4. Oblong, 
rounded at both ends, ventral margin entirely convex and not at all 
indented, covered with decussated prickly strie which posteriorly 
form distant radiating rows of prickles (but not ribs) : margin above 
the hinge reflected and covered with an elongated accessorial plate : 
a toothlike process on the hinge, ascending obliquely and anteriorly. 
3..2.—Hurope. 
P.Parva.* Mont.p. 22.t.1.f.7,8.—D. p. 38.—W. t. 2. f. G. 
—Turt. Biv. p.9.—P. Dacrytorpes, Lam.4. Ovate, beaked poste- 
riorly, rough with reticulated rather prickly striz except anteriorly ; 

* P. Oblongata Say is probably this species, although its beak 
and the number of its accessory valves is not mentioned. 
P. Catiosa. Lam. 8. Ovate-oblong, sinuated, posteriorly with 
curling strize, anteriorly smooth ; hinge plate rather prominent and 
globose.— Bayonne. From the brevity of this description, I am 
unable to recognize the species, the figures quoted by Deshayes 
however (List. t. 433. and Brooke, t. 1. f. 7, 8.) are distorted 
Dactyli. 
