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TERTIARY FAUNA OF FLORIDA 



Genus Egeria Roissy. 



Section Egeria s. s. Type E. paradoxa Born. 



The characters are recounted above in detail ; the dentition is rude, the 

 laterals small and short, the pallial sinus small, the shell large and heavy. 



Section Profischeria Dall.* Type Fischeria Delesserti Bernardi. West 



Africa. 



Shell small and relatively thin, the anterior and posterior right cardinals 

 obsolete in the adult, the middle cardinal bifid ; in the left valve the middle 

 cardinal is obsolete, the two others bifid ; the laterals are slender and elongated, 

 the bevelled edges of the left valve fit into sockets above them ; the pallial sinus 

 is relatively larger. 



This section differs from Egeria by characters which might be expected in 

 a small and thin representative of a rude and large genus. The name Fischeria 

 applied to it by Bernardi had been used in Diptera thirty years earlier. 



The relation to Iphigenia Schumacher, of the Donacidce, which appeared to 

 some of the older writers, is superficial. No species are yet known from our 

 Tertiaries. 



FAMILY SPH^ERIID^. 



Cardinal teeth not exceeding two in each valve, and exhibiting -a cessation 

 of development at an early stage. 



Genus SPH./ERITJM Scopoli. 

 Spharium Scopoli, Intr. ad Hist. Nat., p. 397, type Tellina cornea Linne; Gray, P. Z. S., 



1847, p. 184, No. 555; Ann. Mag. N. Hist, 2d Ser., xi., p. 39; Prime, Mon. Am. 



Corbiculada, p. 32, 1865 ; Westerlund, Patina Palaearct. reg., vii., p. 5, 1890. 

 Nux (Anonymous) Mus. Calonnianum, p. 59, 1797. Tellina cornea Linne. 

 Cyclas (sp.) Bruguiere, Enc. Meth., 3me livr., pi. ccci., 1798. 

 Cyclas Lamarck, Prodrome, p. 84, 1799, Tellina cornea Linne ; Bowdich, Elem. Conch., 



ii., p. 8, fig. 22, 1822, C. rivicola; Raug, Man. des Moll., p. 312, 1829; Deshayes, Enc. 



Meth., ii., p. 36, 1830; Schlueter, Verz. Conch., p. 34, 1838; not Cyclas (Bruguiere) 



Link, 1807. 

 Cornea Megerle, Entw. ein. neues Syst, p. 56, 1811, Tellina cornea Linne {Cornea com- 



munis Megerle). 

 Amesoda Rafinesque, Ann. Gen. des Sci. Phys., Bruxelles, 1820, p. 319, Cyclas similis 



Say. 



*This and the other names in Cyrenacea proposed by the present writer first ap- 

 peared in Proc. Biol. Soc. of Washington, xvi., pp. 5~8, February 21, 1903. 



