TRANSACTIONS OF WAGNER 

 II08 



TERTIARY FAUNA OF FLORIDA 



of the shell; the posterior ribs (12) have the long slope forward and an 

 abrupt slope on the posterior side, and are surmounted on the posterior side 

 by a supplementary costa from which spring obliquely set spinules ; the 

 posterior ribs near the hinder margin are again more crowded. 



Cardium (Papyridea) spinosum var. aspersum Sowerby. 

 Cardium aspersum Sowerby, P. Z. S., 1833, p. 85. 



Recent on the Pacific coast of America from the Gulf of California south 

 ' to Panama and Santa Elena. 



Shell with about the same number of ribs as the preceding and having them 

 similarly divided into groups, but with the bottoms of the channels flattish 

 rather than filiform, the ribs themselves more elevated, rounded and strong, 

 and the imbrications and spinules coarser and more distant ; the microscopic 

 granulations irregularly distributed, very sparse and distant, often wholly 

 absent. 



Cardium (Papyridea) spinosum var. Turtoni Dall. 

 Cardium bullatum E. A. Smith, Marine Moll, of St. Helena, P. Z. S., 1890, p. 302. 



Pliocene of the Caloosahatchie River, Florida ; recent at St. Vincent, Cape 

 Verde Islands, and St. Helena (Turton). 



Shell with about fourteen anterior, sixteen to twenty-three medial, and 

 eight to eleven posterior ribs, the interspaces with a well-marked flattish thread 

 between two sharp grooves; the spinules and imbrications as in var. spinosum; 

 the medial ribs triangular in section, the apex of the triangle inclining for 

 the most part slightly towards the anterior end of the valve and surmounted 

 by a single row of close-set minute granules, giving it a serrate appearance, 

 and elsewhere polished and destitute of granulation ; the form and serration 

 of the ribs obvious to the naked eye ; concentric striation regular and fine. 



It is a singular thing that the Pliocene fossil should be of the type now 

 confined to the eastern Atlantic ; the well-known fact that many of the living 

 deep-water mollusks of the Antillean area are represented in the Italian Plio- 

 cene and not in our own may be, in some manner to be determined later, of 

 an analogous nature. 



Cardium (Papyridea) semisulcatum Gray. 

 Cardium semisulcatum Gray, Ann. Phil., ix., p. 137, 1825; E. A. Smith, Challenger Biv., 



p. 162, 1885. 

 Cardium ringiculum Sowerby, P. Z. S., 1840, p. 106; Conch. 111. Cardium, p. 2, pi. 48, 



fig. ii, 1841. 



