MAZATLAN BIVALVES 41 



Ralhke, Siemaschke. Santa Barbara, abundant, NuttalL 



Mazatlan : not common ; Upool Col. 



Tablet 129 contains 6 pairs and 2 valves, shewing variations. 

 The smaller valve may be T. cicercula, Phil., in Zeitschr.fur 

 Mai. Feb. 1846, p. 19. I cannot however separate it from 

 S. carnaria, of which it appears the young. The description of 

 T. cicercula exactly applies to this, which is the left valve. 

 Menke in quoting the species among Melchers' Mazatlan Shells, 

 Zeitschr.f. Mai. 1847, p. 188, no. 53, says that it is only the left 

 valve which possesses the sculpture in question : so does the left 

 valve of T. carnaria, and that alone. Menke loc. cit. describes a 

 new species, T. areolata, from the West Indies, intermediate 

 between T. cicercula and T. carnaria, with a similar smooth 

 space on the left valve. Philippi also describes from Mazatlan 

 (loc. cit.) T. lenticula, T. dichotoma, and T. ervilia. In his 

 Abbil. Conch, for Aug. 1846, p. 24, he also gives the ancient 

 T. pisiformis, Linn, (along with Diplodonta semiaspera) as 

 common to Mazatlan and the Caribbean Sea. Mazatlan must 

 be rich in Strigillse, according to Philippi ! 



67. PSTRIGILLA LENTICULA, Phil. 



TeUina lenticula, Phil, in Zeitsch.f. Mai. 1846, p. 19. 



Tablet 130 contains a broken specimen which probably be- 

 longs to this species, which, says Philippi, while agreeing in 

 form and size with T. pisiformis, has the sculpture of Lucina 

 digitaria. It may however belong to Lucina eburnea, Rve, 

 Conch. Icon. pi. 8, f. 49, found in sandy mud, 11 fm., St. Elena 

 and Panama, Cuming. 



Hob. Mazatlan, Philippi. ? Do. fragments, off the back of 

 Chama ; L'pool Col. 



68. , sp. ind. 



Tablet 131 contains a fragment of a thin shell of moderate 

 size, perhaps a Psammobia, (possibly an unknown Donax,) 

 strongly angulated, with very fine, slightly rugose stride, 

 coarser on the angular part. It is white, slightly bordered 

 with orange. 



Hab. Mazatlan ; confined in the mouth of Trivia sanguinea ; 

 L'pool Col. 



