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TERTIARY FAUNA OF FLORIDA ^ 



Genus UOCONCHA Morch. 



Lioconcha Morch, Cat. Yoldi, ii., p. 26, 1853 (Venus castrensis Linne); H. and A. 

 Adams, Gen. Rec. Moll., ii., p. 429, 1857; Romer, Mon. Venus, i., p. 147, 1868; 

 Stoliczka, Cret. Pel. India, p. 152, 1871 ; Fischer, Man. de Conchyl., p. 1080, 1887. 



Tropical seas of the old world. 



Shell solid, heavy, porcellanous, smooth or concentrically striated, sub- 

 orbicular; lunule sharply circumscribed, impressed; escutcheon absent; liga- 

 ment sunken and almost immersed ; pallial line slightly flexuous ; inner mar- 

 gins smooth ; anterior left and posterior right dorsal margins deeply grooved 

 beyond the hinge-plate to receive the bevelled edge of the opposite valve ; 

 anterior lateral teeth large and strong ; three smooth, stout, entire cardinals in 

 each valve ; periostracum thin and smooth. 



This group was formerly regarded as a subgenus of Circe chiefly on account 

 of its nearly simple pallial line. It is not represented in the American Tertiary, 

 the "Lioconcha" Newcombiana Gabb, which occurs Pleistocene and recent on 

 the Calif "ornian coast, being a species of Chionella. 



Genus MAOROCAT.T.TSTA Meek. 



Macrocallista Meek, Pal. Upper Missouri, p. 179, 1876; type Venus nimbosa Solander; 

 Tryon, Syst. Conch., iii., p. 178, 1884; Fischer, Man. de Conchyl., p. 1079, 1887. 



Chione Gray, Analyst, viii., p. 305, 1838 (Venus chione Linne); P. Z. S., 1847, p. 183; 

 Leach, Syn. Moll. Gt. Brk., p. 302, 1852; not Chione Megerle, 1811, or Gray, 1851. 



Dione Gray, List Brit. An. Brit. Mus., p. 6, 1851; Venus chione Linne; not Dione Gray, 

 1847, or Hiibner, Lepidoptera, 1816. 



Callista Morch, Cat. Yoldi, ii., p. 27, 1853 (Venus chione Linne) ; Romer, Krit. Unters., 

 p. 15, 1857; H. and A. Adams, Gen. Rec. Moll., ii., p. 424, 1857; Romer, Mon. Venus, 

 i., p. 43, 1866; Meek, Pal. Upper Missouri, p. 178, 1876; Tryon, Conch., iii., p. 177, 

 1884; Fischer, Man. de Conchyl., p. 1079, 1887; Bucquoy, Dautzenberg, and Dollfus, 

 Moll, de Roussillon, ii., p. 322, 1893; not Calista (Poli) Leach, Syn. Moll. Gt. Brit, 

 p. 305, 1852. 



Chionella Cossmann, Cat. Illustre bas Paris, i., p. 105, 1886; Fischer, Man. de Conchyl., 

 p. 1080, 1887. Type Cytherea ovalina Deshayes. 



This genus, which contains some of the most elegant of the Veneridce, has 

 been called by names which cannot be retained, all of them having been first 

 proposed with a different use. The first binomial author to utilize the name 

 Callista (which had been one of Poli's quadrinomials) was Leach, who applied 

 it to Venus verrucosa Linne, so that it cannot be used for the present assembly. 



The name Macrocallista of Meek was intended to designate the Venus 



