530 MAZATLAN BIVALVEa 



[Family COEBULID^.]; 



682. ? CoEBULA , sp. ind. (b,) 



Tablet 2518 contains a delicate wkite valve, of regular Arcoid 

 shape, extremely thin, with very faint radiating lines. Hinge 

 with pit and tooth scarcely perceptible. 



Sah. — Mazatlan ; extremely rare, off Spondylus ; L'pool Col. 



683. Sph^nta , sp. ind. 



Tablet 2519 contains a valve differing from Sph. fragilis in 

 having strong sharp concentric ridges, with a few radiating 

 lines. 



JSaJ.— Mazatlan ; extremely rare ; off Spondylus ; L'pool Col. 



684. PSph^nia , sp.ind. 



Tablet 2520 contains 'the remains of a shell of Sphsenoid 

 growth, but of Myoid hinge, which was nestling in an empty 

 Balanus on Uvanilla olivacea. 



Sab. — Mazatlan ; extremely rare ; L'pool Col. 



[Family PANDOEID^.] 



693* ? Lyonsia , sp. ind. 



Tablet 2528 contains a minute white valve, not perfect, of 

 Eupellaroid shape, but with a hinge and texture nearer to 

 Lyonsia. Outside with faint irregular concentric ridges, end- 

 ing here and there, on the posterior dorsal margin, in a decided 

 spine. Inside with a slight anterior tooth-like process, and a 

 small cartilage bed. It appears to be minutely punctate. 

 When perfect, it would have measured long. '04, lat. "05, 

 alt. -012. 



Sab. — Mazatlan ; one valve in the frond of Murex nigritus ; 

 L'pool Col. 



* This species, with No. 694, hare just been foasd in carefully cleaning: the 

 fonds of M. nigritu3, along with another valve of Leda Elenensis, Gouldia varians, 

 Lucina Mazatlanica, Alaba supralirata, &c. The numbering of the species 

 is arranged so as not to break the correspondence with the list in the British 

 Aiseociatiou Eeport, already printed. 



