TRANSACTIONS OF WAGNER 

 1 174 



'^ TERTIARY FAUNA OF FLORIDA 



Subgenus MILTHA H. and A. Adams. 



This group is very abundant in the Eocene Tertiaries, dwindling until it is 

 represented in existing faunas, so far as known, only by two living species, one 

 in the Gulf of California and one in the Indian Ocean. 



The typical section comprises species in which the cardinal teeth are clear- 

 cut and well developed. It, again, comprises three groups of species represented 

 in most horizons down to the Pliocene and two of which are known to survive. 

 These are : 



A. Species of which the surface sculpture is characterized by concentric 

 lamellation like P. (M.) disciformis and hillsborocnsis of Heilprin. 



B. Species compressed, high, and with fine concentric striation, like P. (M.) 

 Childreni Gray and caloosaensis Dall. 



C. Species with sculpture similar to the last but more convex and elongated 

 and with a somewhat sinuous basal profile, like P. (M .) pandatus Conrad and 

 Voorhoevii Deshayes. 



Phacoides (Miltha) claibornensis Conrad. 



PLATE 50, FIGURE 18. 



Cyclas claibornensis Conrad, Am. Journ. Conch., i., pp. 8, 146, 1865. 



Lucina claibornensis Aldrich, Geol. Surv. Ala., Bull. No. ii., p. 57, 1886 (Gregg's Land- 

 ing) ; Meyer, Bericht Senckenb. Naturf. Ges., 1886, p. 16, 1887 (Jackson, Miss.) ; 

 Gregorio, Mon. Claiborne, p. 204, 1890. 

 f Lucina arnica Gregorio, Cossmann, Notes Compl., p. 12, 1894. 



Eocene of Lisbon Bluff, and of the lowest bed at Claiborne Bluff, Alabama, 

 the Aquia formation at Pope's Creek, Maryland, and of Jacksonian of Gar- 

 land's, Clarke County, Mississippi (a variety?), and Jackson, Mississippi. 



A figure of this hitherto unfigured species is given, as in the absence of 

 one it can hardly be identified. It belongs to group A. of the section. The 

 form from the Jacksonian is apparently wider and with shorter and more 

 prominent dorsal areas, but I have not sufficient material to be able to positively 

 differentiate it from that of the Lisbon horizon. 



Phacoides (Miltha) pandatus Conrad. 

 Lucina pandata Conrad, Am. Journ. Sci., xxiii.. p. 343, Jan., 1833 ; Fos. Tert. Form., No. 



4, p. 40, Oct., 1833 ; Orbigny, Prodr. Pal., p. 387, 1850. 

 Lucina compressa Lea, Contr. Geol., p. 55, pi. i., fig. 27, Dec., 1833; Aldrich, Geol. Surv. 



Ala., Bull. No. 2, pp. 9, 37, 1886; Gregorio, Mon. Claib., p. 206, pi. xxix., figs, i, 2-5, 



1890. 



