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1487 



TERTIARY FAUNA OF FLORIDA h ' 



Section Astarte s. s. 

 Dental formula Uo - 101010 - 1 , the middle right and two anterior left cardinals 



R. i.oioioi.o 



strong, the others obsolete; valves with convex umbones, subequilateral, the 

 inner margins, when fully developed, crenate. Type A. sulcata Da Costa. 



Section Tridonta Schumacher. 



Like Astarte s. s., but the umbones very anterior, nearly terminal. Type 

 A. borealis Schumacher (= semisulcata Leach). 



PSection Neocrassina Fischer. 



Like Astarte s. s., but the umbones very anterior, nearly terminal. Type 

 A. obliqua (Lam.) Deshayes. 



Section Rictocyma Dall. 



Shell small, with convex umbones ; resembling Astarte, but the concentric 

 waves near the umbones broken, bifid, or irregular; inner margins smooth. 

 Type Crassatella esquimalti Baird. 



Section Ashtarotha Dall, 1903. 



Umbones conspicuously flattened and concentrically sculptured; valves 

 usually smoother outside of the flattened area; otherwise like Astarte s. s. 

 Type Astarte undulata Say. Miocene. 



Section Gonilia Stoliczka. 



Hinge as in Astarte; valves small, lentiform, with divaricate ribbing on the 

 central part of the disk. The large cardinals are bifid. Type Lucina bipartita 

 Philippi (= Astarte bipartita Stoliczka, 1871, not of Sowerby, 1829, = ^. 

 calliglypta Dall, 1903). Recent. 



Section Digitaria Wood. 



Valves rotund ; surface arcuately, obliquely sulcate ; shell small, lentiform ; 

 hinge as in Gonilia; the inner margins more or less tangentially sulcate by 

 the encroachment of the external sulci. Type Tellina digitaria Linne. Woodia 

 Deshayes is synonymous. Recent and Pliocene. 



Section Crenimargo Cossmann. 



Shell thin, like Digitaria, but without external oblique sulci, the tangential 

 sulcations of the inner margin present and resembling those of Transennella ; 

 hinge as in Digitaria. Type C. inatquicrenata Cossmann. Eocene of Paris. 



Subgenus Goodallia Turton. 



Shell small, smooth, the hinge-teeth reduced by the absence of the anterior 



