TRANSACTIONS OF WAGNER 

 1294 



TERTIARY FAUNA OF FLORIDA 



radial sculpture is of faint striation on the ventral side of the lamellje, insuffi- 

 cient to flute them ; hinge as usual, the two anterior left and posterior right 

 cardinals grooved distally, the posterior adductor scar larger than the anterior 

 one ; the pallial sinus small, sharply angular ; interior marginal crenulation 

 fine and regular. Length 24.5, height 20.5, diameter 14.0 mm. 



This interesting species is, as it were, just launched on its career towards 

 the typical Lirophora; a trifle might have given it the same impetus towards 

 Chamelea. 



Chione (Lirophora) Burnsii Dall. 



Plate 41, Figures 4, 11; Plate 42, Figure sa. 



Venus (Anaitis) Burnsii Dall, Trans. Wagner Inst., iii., p. 1198, pi. Ixi., figs. 4, 11, 1900. 



Oligocene of the Chipola horizon at Alum Bluff and on the Chipola River ; 

 Burns and Dall. 



Shell subtrigonal, heavy, moderately convex, with low prosogyrate beaks 

 over a striated cordate lunule, with the escutcheon elongate, nearly smooth, 

 bounded by a well-marked keel ; beaks with a few distant, low, concentric 

 lamellae ; later the ribs become greatly thickened and recurved with narrower 

 interspaces or more commonly confluent, suddenly pinched out behind, where 

 they rise in thin, elevated foliations, and below the lunule in front are some- 

 what similar but more crowded ; these ribs are crossed by faint radial stria- 

 tions sharper towards the beaks but not visible in the interspaces ; hinge nor- 

 mal, teeth entire, adductor scars subequal ; pallial sinus angular, small. 

 Length 34, height 26, diameter 16 mm. 



Except in the radial striation this species recalls the recent C. Kellettii 

 Hinds of the Pacific coast fauna. The ribbed form is close to C. glyptocyma 

 of the Oak Grove sands, but may be distinguished by the sculpture of the beaks. 



Chione (Lirophora) mactropsis Conrad. 

 Gratelupia? mactropsis Conrad, House Ex. Doc. 129, Rep. of W. P. Blake, App., p. 18, 



July, 1855 ; Pacific R. R. Reps., v., p. 328, pi. vi., fig. 54, 1856. 

 Chione sulcata Gabb, Proc. Acad. Nat. Sci. Phila. for i860, p. 567, 1861. 



Eocene ? and Oligocene of the Isthmus of Darien, Blake ; of Gatun and 

 Vamos-a-vamos on the line of the Panama Canal, Agassiz; 10.5 kilometers 

 west of Colon, R. T. Hill; Chiriqui, Dr. John Evans (Gabb). 



This species was represented by an internal cast in W. P. Blake's collec- 

 tion, which was described and figured as above cited by Conrad. It is a species 

 closely related to C. Burnsii, but more compact and rough, the foliaceous area 



