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589 



TERTIARY FAUNA OF FLORIDA 



shaped teeth; chondrophore small, subumbonal ; the rostrum without an 

 internal ridge, the pallial sinus small. Lon. 5.2, alt. 3, diam. 2.5 mm. 



This interesting little species appears to be rather common in beds of the 

 Wahtubbee horizon. It differs from L. robitsta Aldrich in details of sculpture, 

 especially on the escutcheon. 



Leda flexuosa Heilprin. 

 Plate 3S, Figures 5, 5 a. 

 Leda flexuosa Heilprin, Trans. Wagner Inst., i., p. 119, pi. 16, fig. 66, two views, 1887. 



Oligocene silex beds of Ballast Point, Tampa Bay, Florida ; Heilprin 

 and Dall. 



This species was imperfectly represented by the original figures, and at 

 the suggestion of Mr. Willcox new figures of it have been included here. 



Leda hypsoma n. s. 

 Plate 32, Figure 2. 



Miocene of the Natural Well, Duplin County, North Carolina ; Burns. 



Shell small, polished, compressed, with the rostrum short, pointed, and 

 gaping at the end ; sculpture of flattened, wide, concentric waves or riblets, 

 with their dorsal slope steeper; these waves are obsolete over the anterior 

 dorsal and terminal part of the valves, and wholly absent from the rostrum ; 

 beaks nearly central, plump, low ; lunule very narrow, bordered by an im- 

 pressed line ; escutcheon wider, bordered by a large, rounded rib on each side, 

 the area longitudinally grooved; rostrum shghtly recurved; base arcuate; 

 interior polished, with a small pallial sinus ; fourteen anterior and about eleven 

 posterior teeth ; the chondrophore minute, subumbonal ; the rostral channel 

 not divided by a ridge. Lon. 5.5, alt. 3.2, diam. 1.5 mm. 



This species recalls Nuculaiia linifcra Conn, but is larger and more 

 elongated, with a more conspicuous rostrum. 



Leda dodona n. s. 



Plate 32, Figure 6. 



Oligocene of the Oak Grove sands, Santa Rosa County, Florida ; Burns. 



Shell small, solid, slightly inequilateral, polished, strongly concentrically 



sculptured ; sculpture of elegant, even, high, blunt-edged, slightly recurved 



lamellae, with deeply excavated, wider interspaces, which are striated by the 



lines of growth ; the sculpture ends anteriorly at the margin of the lunule. 



