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815 



TERTIARY FAUNA OF FLORIDA 



Pholas (Thovana) campechiensis Gmelin. 

 PJwlas campechiensis Gmelin, Syst. Nat., vi., p. 3216, 1792; Hanley, Descr. Cat. Rec. 



Sh., p. 6, pi. 9, fig. 44, 1842. 

 Pholas oblongata Say, Journ. Acad. Nat. Sci., ii., p. 320, 1822; not of Tiiomey and 



Holmes, Pleioc. Fos. S. Car., p. 103, pi. 24, fig. 5, 1858. 

 Pholas candeana Orbigny, Moll. Cubana, p. 215, pi. 25, figs. 18-19, '^45- (Young shell.) 

 Pleistocene of South Carolina and Florida ; recent from Cape Hatteras, 

 North Carolina, to Brazil. 



This species is distinguished from the following one by the proportions 

 and extent of the umbonal processes, which differ markedly in the two forms. 



Pholas (Thovana) producta Conrad. 

 Pholas oblongata Tuomey and Holmes, Pleioc. Fos. S. Car., p. 103, pi. 24, fig. 5, 1858; 



not of Say. 

 Pholas prodiicta Conrad, Proc. Acad. Nat. Sci. Phila. for 1862, p. 571, 1863. 



Miocene of the Sumter District and Peedee River, South Carolina ; Plio- 

 cene of the Waccamaw River, South Carolina ; Holmes and Johnson. 



In this species the umbonal reflection is considerably longer in proportion 

 than in the Pleistocene shell, and the anterior space between the reflected 

 edge and the exterior of the valve in front of the umbo and below the level 

 of the septa is much smaller and less conspicuous. The ribbing of the 

 present species is less sharp and continuous. 



Pholas (Thovana?) Memmingeri Tuomey and Holmes. 

 Pholas Meinmingcri 1 . and H., Pleioc. Fos. S. Car., p. 104, pi. 24, fig. 6, 1858. 



Miocene of the Sumter District, South Carolina ; Tuomey and Holmes. 

 This species recalls Zirfcea, but is said by the authors cited to have a 

 septate umbonal reflection. It is subtruncate behind and differs widely from 

 any of the other species, but has been unaccountably omitted from all the 

 checklists. 



Genus BARNEA (Leach MS.) Risso. 

 Barnea Risso., Hist. Eur. Mer., iv., p. 376, 1826. Type B. spinosa Risso (= P. Candida 



Linne). 

 Holopholas Fischer, Man. de Conchyl., p. 1133, 1887. 

 Pholas Lamarck, 1801 ; Tryon, 1862 ; not Lamarck, 1799. 

 Cyrtopleura Tryon, Mon. Pholadacea, p. 73, .1862. 



Shell with the space below the umbonal reflection not septate; accessory 

 plates not exceeding two in number. 



