1904.] NATURAL SCIENCES OF PHILADELPHIA. 553 



to identify them as the young of any larger species, although I am 

 disposed to believe that it will be found to reach a larger size. The 

 small number of radial riblets is a prominent feature of the sculpture. 

 Venus imbricata Sowerl^y is a longer species with the lamellae obsolete 

 in the intervals. V. scahra Hanley is unlike in sculpture, but both of 

 these seem related to C. micra. 



Chione hizenensis n. sp. PI. XLI, figs. 1, 2. 



Shell small, shortly ovate, compressed, yellowish, irregularly macu- 

 late with reddish-brown. Beaks slightly in front of the middle, small 

 and projecting but slightly. Anterior end broadly rounded, posterior 

 end narrower and somewhat tapering. Sculpture of about 42 rounded 

 radial riblets, a little wider than their intervals, becoming very small 

 at the two ends of the series, though they are largest at the anterior 

 end of the shell. The ribs of the anterior half of the shell are divided 

 by a narrow median groove, on the lower half of each rib. These 

 radial riblets are crossed by many regular narrow concentric ridges, 

 higher on the ribs than in the intervals; the whole producing the effect 

 of a tiled roof. The interior is white, usually with a drop-shaped 

 purple-brown streak at one or both ends, and more or less extensive 

 stains of similar tint in the cavity. The pallial sinus is short and 

 rounded. The edge is crenulated in harmony with the riblets along the 

 posterior half of the lower margin, but along the anterior half there 

 are about two denticles to each rib. The two ends are very finely 

 crenulate, and the anterior side of the dorsal margin is crenulate par- 

 allel to the longest axis of the shell, the posterior dorsal margin being 

 smooth. The two obliquely triangular cardinal teeth in the right 

 valve and the short median tooth in the right valve are slightly bifid. 



Length 10.8, alt. 8.6, diam. 5 mm. 



Hirado, Hizen. Types No. 86,281, A. N. S. P., from No. 1,0386 of 

 Mr. Hirase's collection. 



V. costellifera Adams and Reeve (Zool. "Samarang," Moll., p. 79 

 pi. 21, fig. 18) is a larger, differently colored form from the Philippines, 

 which seems from the description and figure to be closely related, but 

 the scales are stated to be semilunar, while in C. hizenensis they are 

 straight. V. marica differs in sculpture and in the pattern of internal 

 crenulation of the valve margins. 



Pitar sulfurea n. sp. PI. XXXIX, figs. 7, 8, 9. 



The shell is triangular-oval, inflated, solid; pale sulphur-tinted out- 

 side, and distinctly, very finely striate throughout, with some impres- 

 sions indicating former growth-arrests. Beaks full and prominent, 



