314 BULLETIN OF THE 
Corbula Swiftiana C. B. Apams. 
Corbula Swiftiana C. B. Adams, l. c., p. 286, 1852; Dall, Bull. M. C. Z., IX. p. 114, 
1881. 
Plate Il. Figs. 5a-5c. 
Habitat. Sigsbee, off Havana, 182 and 450 fms., living; off Sombrero, 72 
fms. 
Identified and figured from the types. Lon. of shell 10.4 mm. 
Corbula Dietziana C. B. Apams. 
Corbula Dietziana C. B. Adams, 1. c., p. 235, 1852 ; Dall, Bull. M. C. Z., IX. p. 114. 
Corbula Blandiana C. B. Adams, 1. c., p. 234 (= young stage of C. Dietziana, Ad.). 
Plate I. Figs. 5, 5a,5b. 
Habitat. West coast of Florida, 30 fms.; off Sombrero, 72 fms.; Barbados, 
100 fms.; Gordon Key, 68 fms. 
Identified and figured from the types. Lon. of shell 10.7 mm. 
Corbula disparilis D’Orzieny. 
Corbula disparilis D’Orb., 1846; Dall, Bull. M. C. Z., IX. p. 115, 1881. 
Corbula Philippii Smith, Chall. Rep., p. 33, pl. vii. figs. 4, 4a, 4b, 1885. 
Corbula operculata Philippi, Zeitsch. Mal., V. p. 18, 1849. 
Plate I. Figs. 4, 4a, 4b. 
Habitat. Off the west coast of Florida, 30 and 50 fms.; Station 12, 36 fms.; 
off Sombrero, 72 fms. ; Station 36, 84 fms.; Barbados, Station 287, etc., 74 to 
100 fms.; Sigsbee, off Havana, 127 and 450 fms.; Station 2, 805 fms. 
This species closely resembles several exotic and fossil forms; among the 
former may be mentioned Corbula nucleus L.; among the latter, C. oniscus 
Conrad (Eocene of the United States) and C. parsura of Stoliczka, from the 
Trichinopoly beds (Cretaceous of India), as well as some from the Danish 
ligniferous strata. 
Those who consult D’Orbigny’s figures will observe that they differ from the 
shell figured by my friend Smith in representing the valves as nearly equal, 
and also in the absence of the epidermal radiations on the smaller valve and 
the carina on the larger one. But I infer from D’Orbigny’s remarks, that he 
had only separated valves, and probably those which had lost their epidermis; 
and it is probable that the artist represented two valves together which did not 
belong together. The carina is a variable feature in this species, as in C. nu- 
cleus. At all events, the specimens I have are certainly the same as C. Phi- 
lippit Smith, and I believe them to be the species described by D’Orbigny. 
