1895. PROCEEDINGS OF THE NATIONAL MUSEUM. 19 



somewliat larger, the pallial line set in below it, somewbat irregular 

 but not forming a distinct angular sinus ; margins of valve thin, smooth. 

 Height, 63; length, 110; diameter, 50 mm.; vertical of the beaks, 24 

 mm. behind the anterior end of the shell. 



U. S. Fish Commission station 3000, oft' Concepcion l>ay, in the Gulf 

 of California, in 857 fathoms, mud; temperature, 3S° F. 



This relatively enormous shell was obtained only as a number of 

 fresh Aalves without the soft parts but from the shell characters it 

 can hardly be anytliing but a giant CaJhcardia. 



CALLOGONIA ANGULATA, new species. 



Shell elongate, moderately inflated, the surface as in the other species; 

 the anterior end rounded, shorter; the posterior end produced, pointed; 

 ligament short, set in a groove; the posterior dorsal border marked by 

 two obscure ridges radiating from the beak, the outer one of which 

 terminates at the posterior extreme of the valve, angulating the margin ; 

 the epidermis is denser and lamellose in the interspaces between these 

 ridges; lunule obscure; basal margin nearly straight, rounded up 

 toward the ends; beaks low, anterior; interior white, with some radial 

 striie; hinge narrow; right valve with two low cardinals coalescent 

 above, and a third, higher, springing between them; pallial line 

 distinct, with an angular, rather short, sinus. Height, 35; length, 58; 

 semidiameter, 10 mm.; the vertical of the beaks, 18 mm. behind the 

 posterior end of the shell. 



U. S. Fish Commission station 3392, in 1,270 fathoms, hard bottom; 

 temperature, 36.4°; in the Gulf of Panama. 



A single right valve of this distinct species was collected as above, 

 and differs from ^Callocardi a especially by its angular pallial sinus. 



PERIPLOMA STEARNSII, new species. 



Shell suborbicular, thin, whitish, with pale straw-colored epidermis, 

 sculptured with faint concentric irregularities harmonizing with the 

 lines of growth and by very fine pustules arranged in radiating lines, 

 stronger and more adjacent near and upon the rostrum; beaks not 

 prominent, fissured; left valve slightly less convex than the right; ros- 

 trum about two-thirds as wide as the shell, not strongly differentiated, 

 but with the epidermis coarser, and, especially on the left valve, more 

 raised and wrinkled, and the basal margin slightly excavated; interior 

 faintly pearly; pallial sinus large, rounded, shallow; chondrophore 

 strong, spoon-shaped, inclined obliquely forward. Length of shell, 40; 

 height, 35.5; diameter of the riglit valve, mm.; the rostrum 20 mm. 

 wide, rounded, and moderately gaping; total diameter, 18 mm. 



U. S. Fish Commission station 30;'.4, in 24 fathoms, mud; oft' Point 

 Fermin, at the head of the Gulf of California. 



This difters from P. discus, Stearns, in the radial arrangement and 

 larger size of its surface granules, its wider rostrum and more com- 

 pressed form. It needs no comparison with other species. 



