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783 

 TERTIARY FAUNA OF FLORIDA 



Anomia microgrammata n. s. 

 PLATE 35, FIGURE n. 



Oligocene of the Chipola beds at the Chipola River and the lower bed at 

 Alum Bluff, Florida ; also at Ballast Point, Tampa Bay, Dall, Burns, and 

 Willcox ; and at Bowclcn, Jamaica, Henderson and Simpson. 



Shell small, irregular, characterized by a fine, almost microscopic, close- 

 set radial striation covering the whole surface and flaring away from the 

 medial line of the valve in a somewhat wavy manner ; the two lower scars on 

 the left valve are subcqual and side by side, the major byssal scar larger, oppo- 

 site the medial line between them ; the beak of the left valve is some distance 

 within the margin, and the surface where worn appears smooth ; the striation 

 is only visible under a lens in most cases. Alt. 17, lat. 25 mm. 



This species is recognizable by its fine, almost divaricate striation, which 

 does not break into pustules near the beaks, as in the larger and more 

 coarsely sculptured A. cpliippioidcs. 



The specimens from Bowden have a still finer and often partially obsolete 

 striation. They form the variety indccisa (Guppy, MS.). 



Anomia floridana n. s. 

 PLATE 35, FIGURE 7. 



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



Shell of moderate size, usually rather convex, the surface irregular, obso- 

 letely microscopically radially striated, more or less irregularly feebly pustular 

 and with obsolete, broken, feeble radial plications; the minor byssal scar is 

 above and slightly further back (about half its own width) than the adductor 

 scar of the same size ; the major byssal scar is rounded and much larger, 

 situated directly above the minor one, so that the three scars are nearly in 

 one dorso-ventral line ; the beak of the left valve is at the cardinal margin. 

 Alt. of largest specimen 35, lat. 39 mm. 



This species is intermediate in size and character between A. inicrognvn- 

 niata Dall and A. Ruffini Conrad. It is smaller and less sculptured than 

 the latter, which also wants the microscopic striation; it is larger, less sharply 

 striated, and has the beak and scars situated differently from the former. 

 Many of the speeimens still retain some of the original greenish coloration. 



The only other Oligocene species described from the North American 

 and Antillean regions is the . /. iimltonata Guppy, from Trinidad (Proc. U. S. 

 Nat. Mus., xix., No. 1 1 10, p. 235, pi. 30, fig. 6, 1896), which is small, with 

 minute pustulation but no radial striation. 



