TRANSACTIONS OF WAGNER 

 1082 



TERTIARY FAUNA OF FLORIDA 



scribed. From the description it would appear to resemble C. isocardia. In 

 the Oligocene the fauna is much richer. We have C. (T.) dominicense Gabb, 

 1873, from St. Domingo, easily known by its sixty ribs; C. (T.*) lingualeonis 

 Guppy, 1866, from Bowden, Jamaica, a species allied to the recent C. Belcheri 

 of the Gulf of California, but with more numerous and less elevated ribs, 

 C. (T.) inconspicuum Guppy, and a number of undescribed species. The 

 National Collection contains fragments of a large flat-ribbed species with narrow 

 wrinkled interspaces, not unlike C. marmoreum Lam., and of another species 

 also large and strong with narrower, keeled-muricate ribs, both from Bowden, 

 which may furnish better specimens later on. From the Chipola horizon at 

 Alum Bluff, Chattahoochee River, Florida, comes another species with very 

 narrow imbricate ribs and much wider wrinkled interspaces, only represented 

 in the collection by a fragment. 



Cardium (Trachycardium) inconspicuum Guppy. 



Cardium inconspicuum Guppy, Quart. Journ. Geol. Soc., London, vol. xxii., p. 293, pi. 

 xviii., fig. 12, 1866. 



Oligocene of the Bowden, Jamaica, marl, and of the Chipola marl, Calhoun 

 County, Florida. 



This species really has a little resemblance to C. subelongatum Sowerby, 

 and probably Gabb confused this with C. lingualeonis Guppy when he placed 

 (wrongly) the latter name as a synonym under C. subelongatum. The species 

 actually labelled by the last-mentioned name in Gabb's collection are quite 

 a different thing again, as will shortly be shown. 



The present species has from thirty-six to forty-two ribs, which, when 

 they preserve their outer coat, have a beautiful close concentric threading 

 over the whole shell, except the ribs of the posterior area, which are smooth 

 and polished ; the loops of the threads as they pass over the body ribs (as 

 usual in Cardium) are convex towards the umbones. When this coating is 

 removed by wear the tops of the ribs will be flat and polished while their sides 

 show fringing wrinkles. If erosion attack the second surface, the structure of 

 the shell will reproduce pretty faithfully the reversed loops of the original 

 outer coat. 



Cardium (Trachycardium) dominicanum n. sp. 



PLATE 48, FIGURE 16. 



Cardium subelongatum Gabb, Geol. St. Dom., p. 250, 1873 (syn. exclus.) ; not of Sowerby, 

 P. Z. S., 1840. 



