ball: mollusca and brachiopoda. 417 



Vesicomya ovalis Dall. 



Callocardia ovalis Dall, Proc. U. S. Nat. Mu8., 1896, 18, p. 18. 



Shell resembling the F. lepta Dall, but smaller, more oval, the posterior dorsal 

 border more arched, the proportional inflation greater, the lunule wider, the liga- 

 ment proportionally and actually longer, the epidermis more adherent and without 

 projecting fringes or lamellae ; internally the teeth are smaller and more feeble, 

 and the pallial line recedes less at the posterior adductor scar. Height, 26 ; 

 length, 36; diam. 16 mm.; the vertical of the beaks 8 mm. behind the anterior 

 end of the shell. 



U. S. S. "Albatross," station 3360, in the Gulf of Panama, in 1672 fathoms, 

 sand ; temperature 36°.4 F. U. S. N. Mus. 106,898. 



Vesicomya donacia Dall, n. sp. 



Plate 17, figures 9, 13. 



Shell swollen, cuneate, inequilateral, chalky white, covered with a pale oliva- 

 ceous periostracum, finely concentrically striated; beaks high, inflated, markedly 

 prosocoeloua with a broadly cordate lunular space circumscribed by a strongly 

 impressed line ; ligament long, black, on a thin lamellar nymph ; anterior end 

 rounded, attenuated, short; posterior end longer, attenuated, slightly arcuate 

 and obgcurely rostrate ; hinge Hue and base subequally arcuate ; hinge in the 

 left valve with two undifl"erentiated cardinal teeth almost parallel with the hinge 

 line above them, from which they are separated by a shallow, widely V-shaped 

 socket for the tooth of the right valve ; under the nymph, and of about equal 

 length, the hinge line shows an elongated narrow ridge, simulating a pseudolateral 

 tooth; interior dull white, yellowish in the middle of the disk; margins and 

 pallial line entire; the muscular scars distinct. Lon. 22; alt. 16.5; semi-diam- 

 eter (left valve), 7.0 mm. 



U. S. S. " Albatross," station 3392, Gulf of Panama, in 1270 fathoms, hard 

 bottom, temperature 36°.4 F. U. S. N. Mus. 122,929. 



Only one left valve was obtained, but the form is sufficiently unlike the other 

 species to be readily recognizable. 



Vesicomya stearnsii Dall. 



Callocardia stearnsii Dall, Proc. U. S. Nat Mus., 1S95, 17, p. 693, figs. lA, IR; 

 1896, 18, p. 17. 



U. S. S. "Albatross," station 3316, off Tillamook, Oregon, in 7S6 fathoms, 

 mud, bottom temperature 37°. 3 F. Also at station 3010, Gulf of California, in 

 1005 fathoms, mud, temperature 37°- 6 F. 



The species has much resemblance to F. venusta Dall, from the Atlantic, but 

 VOL. XLni — NO. 6 • 27 



