panamic-pacific pelecypoda 489 



Explanation of Plate 16 



Figure pfage 



1-lb. Lithophaga (Diberos) plnmnla (Hanley) 138 



Figs. 1, la, Length 49.7 mm. Esmeraldas, Ecuador. PRI 25589; 

 Fig. lb. length 32.6 mm, Manta, Ecuador. PRI 25590. 



2-2c. Lithophaga (Myoforceps) aristata (Dillwyn) 137 



Fig. 2, length 29.8 mm. Mafafa, south end of Rey Island, Peari 

 Islands, Panama. PRI 25591; Fig. 2a, length 37.8 mm. Manta. 

 Ecuador; Figs. 2b, 2c, length 39.2 mm. Manta, Ecuador. PRI 

 25592. 



3-3a. Adnla soleniformis panamensis, new subspecies 132 



Length 24.7 mm. Bahia Honda, El Lagartillo, Panama. PRI 25593. 



3b. Adula soleniformis soleniformis (d'Orbigny) 132 



Length 39.5 mm. Manta, Ecuador. 



4-4d. Mnscnins (Gregariella) coarctatns (Carpenter) 129 



Figs. 4, 4c, 4d, periostracum removed, length 22 mm.; Fi?s. 4a, 4b, 

 with periostracum, length 37.6 mm. Manta, Ecuador. PRI 25595. 



5-5c. Botula fnsca (Gmelin) 131 



Length 22.5 mm. Manta, Ecuador. PRI 25596. 



