FREE INSTITUTE OF SCIENCE 



TERTIARY FAUNA OF FLORIDA 



1533 



Phila., i., p. 329, 1843 ; Tuomey and Holmes, Pleioc. Fos. S. Car., p. loi, pi. xxii., 



fig. 2, 1856; Emmons, Geol. Rep. N. Car., p. 300, fig. 231, 1858. 

 Panopcea ahrupta Sowerby, Min. Conch., vii., p. 4, 1829 ; Deshayes, An. s. Vert., vi., p. 



66, 1835 ; Valenciennes, Arch, du INIus. d'hist. Nat., i., p. 36. 1840. 

 Pholadomya (Margaritaria) abrupta Conrad, Proc. Acad. Nat. Sci. Phila., xiv., p. 572, 



1863. 

 Margaritaria ahrupta Meek, Checkl. Miocene Fos. N. Am., p. 12, 1864. 



Miocene of Virginia at Petersburg, Yorktown, Suffolk, and Grove Wharf 

 on the James River ; of Edgecombe County and the Natural Well, Duplin 

 County, North Carolina ; of Sumter, Smith's, Darlington, and Goose Creek, 

 South Carolina. 



Shell nacreous, subsolenoid in form, sparsely radially sculptured ; rounded 

 and slightly gaping in front, abruptly truncate and widely gaping behind ; the 

 beaks submedial, low, ligament external, elongate, on strong nymphs ; hinge- 

 plate continuous, edentulous, narrow ; muscular impressions distinct ; pallial 

 line wide, somewhat irregular, sometimes apparently entire, sometimes with 

 a short angular sinus, at the posterior lower angle of which there is a rather 

 large, strong scar, as if the mantle had had here a specialized area of attach- 

 ment to the shell. This last arrangement occurs in one specimen only, and it 

 is possibly pathological ; at any rate, the specimens with an entire pallial line 

 seem more normal. The surface when unworn is more or less granular and 

 resembles that of Thracia; the interior is brilliantly pearly. The characters 

 of this curious shell have never been fully described, and I have thought it 

 well to call attention to them here. Its relations are certainly most puzzling. 

 I was strongly tempted to place it near Lyonsia, but the arrangement of the 

 ligament is more like that of Thracia and there is nothing to suggest the pres- 

 ence of a lithodesma. Its sculpture and nacre are opposed to affiliation with 

 Panopea even if we disregard the pallial sinus, but there is something in the 

 aspect of it which recalls Allograrnma. 



CLA.SS BRACHIOPODA. 



The non-molluscan classes having been placed in the hands of other students 

 for examination, — Dr. W. B. Clark having undertaken the Echinoderms, Mr. 

 T. W. Vaughan the corals, and Dr. Bagg having the Foraminifera under con- 

 sideration, — the results of their work will appear separately. It was thought 

 best, however, in view of the small number of species, to give a list of the 

 brachiopoda which are met with in the Tertiary strata of our southeastern 

 coastal plain. 



