THE NAUTILUS. 43 



Lucina californica Com-. Modiola (Gregariella) opil'ex 



Lucina mittalli Cour. Say. 



Lucina tenuisculpta Cpr. Septifer bifurcatus Rve. 



Diplodonta orbella Gld. Philobrya setosa Cpr. 30 



Lasea rubra Mont. 30 fathoms. fathoms. 



Lasea rubra Mont., var. sub- Lima orientalis Ad. & Rve. 



viridis Cpr. 30 fathoms. Young, dead. 30 fathoms. 



Kellia laperousii Desli. Pecten latiauritus Conr. Young. 



Kellia suborbicularis Mont. 30 30 fathoms. 



fathoms. Hinnites giganteus Gray. 30 



Milneria minima Dall. fathoms. 



Lazaria stibquadrata Cpr. Monia foliata Brod. In Hinnites, 



Area gradata Brod. 30 fathoms. 

 Mytilus californica Cour. 



NEW SPECIES OF PACIFIC COAST SHELLS. 



BY WILLIAM IIEALEY DALL. 



Trivia atomaria n. sp. Shell minute, of a livid pink, with a sub- 

 stratum of olivaceous cast, the whole giving a pinkish brown effect; 

 form subglobular, with a feeble dorsal sulcus, across which the ribs 

 usually pass without interruption ; in all there are about 18 ribs, 

 with about equal interspaces, which are slightly sagrinate or minu- 

 tely irregularly rugose, though the ribs are smooth ; these ribs form 

 an equal number of fine denticulations on the inside of the outer lip 

 and over the pillar-lip anil internal lobe ; the extremities are very 

 slightly or not at all produced ; the spire is completely obscured. 

 Length 3.2, breadth 2.6, height 2.2 mm. 



Half a dozen specimens of uniform size were dredged in 18 

 fathoms, Panama Bay, by the U. S. Str. Albatross. This is the 

 smallest species I have seen ; even the dwarfs of the allied T. sub- 

 rostrata Gray of the West Indian fauna are larger. 



Trivia panamensis n. sp. Shell small, strongly sculptured, sub- 

 ovate, inflated, with its posterior extremity slightly produced; sculp- 

 tured with about 15 rather sharp-edged strong ribs, of which about 4 

 are intercalary and the others continuous over the shell ; in the 

 middle line of the back they dip slightly but are not interrupted or 

 attenuated ; aperture narrow, strongly and nearly equally toothed on 



