FREE INSTITUTE OF SCIENCE 



1227 

 TERTIARY FAUNA OF FLORIDA ' 



An. s. Vert, v., pp. 572, 573, 1818; Turton, Dithyra Brit, p. 162, 1822; Menke, 



Synop. Meth. Moll., p. 116, 1830; Macgillivray, Moll. Scotl., p. 212, 1844. 

 Orbiculus ft (sp.) Megerle, Entw. Neuen Syst der Schiilth., Mag. d. Ges. Naturf. Freunde, 



p. 58, 1811; Venus exoleta L. (not Orbicula Cuvier, 1798). 

 Arthemis Oken, Lehrb. d. Naturg., p. 229, 1815, after Poli, 1791; (Venus exoleta L.) 



Blainville, Man. Mai., p. 556, 1825; Deshayes, An. s. Vert, ed. ii., vi., p. 295, 1835; 



Philippi, Abbild. u. Beschr., i., p. 171, 1844. 

 Artemis Conrad, Fos. Tert. Form., p. 20, 1832; Anton. Verz., p. 6, 1839; Sowerby, Conch. 



Man., ed. ii., p. 78, 1842; Nyst. Coq. foss. Belgique, p. 183, 1846 (not of Mulsant, 



Asa Defrance (after Leach MS.) in Basterot, Mem. geol. env. de Bordeaux, p. 90, 1825; 



Gray, Ann. Mag. N. Hist., xx., p. 272, 1847. 

 Arctoe Risso, Eur. Merid., iv., p. 361, 1826, Venus exoleta L. 

 Exoleta Brown, 111. Conch. Gt Brit., pi. xx., figs. 2, 3, 1827 (V. exoleta L.) ; Zool. 



Textb., i., p. 450, 1833 ; Conch. Textb., ed. iv., p. 127, 1839. 

 Arctoa Herrmannsen, Ind. Gen. Mai., i., p. 76, 1846. 

 Ccrana Gistel, Naturg. Thierr., p. viii., 1848; Venus exoleta L. 

 Assa. (Leach MS.) Gray, List. Brit An. Brit. Mus., p. 3, 1851. 

 Amphithcea Leach, Syn. Brit Moll., p. 312, 1852. 

 Arthemis Gray, Analyst, viii., No. xxiv., p. 308, 1838. 

 Dosinia Deshayes, Cat. Conch. Brit. Mus., p. 5, 1853 5 Romer, Mon. Dosinia, p. 7, 1862 ; 



H. and A. Adams, Gen. Rec. Moll., ii., p. 430, 1857; Tryon, Str. Syst. Conch., ii., 



p. 180, 1884; Fischer, Man. de Conchyl., p. 1082, 1887; Dall, Bull. 37, U. S. Nat. 



Mus., p. 56, 1889. 

 Not Dosina Gray; Analyst, viii., No. xxiv., p. 308, 1838; P. Z. S., 1847, p. 183, No. 542; 



Venus verrucosa L. 



Animal with a large arcuate foot and closely united siphons. Complete 

 dental formula (the posterior right cardinal, being extremely thin, is often 

 broken off, eroded, or obsolete) L ^^ IO IIiIP. The thick middle cardinals are 



R. loioioi.ioi 



often bifid or excavated. Valves suborbicular, generally compressed, with a 

 long and strong ligament seated in a groove and enfolding a heavy resilium ; 

 lunule small, impressed; escutcheon narrow, nearly linear or absent; hinge- 

 plate broad and thick ; valve-margins smooth ; pallial sinus rather long and 

 usually acute, anterior lateral teeth nearly obsolete and usually simple; sculp- 

 ture usually of elegantly concentric grooves and interspaces, sometimes raised 

 into lamellae at the borders of the lunule and escutcheon, crossed rarely with 

 weak radial threads ; coloration of the recent species rarely disposed in pat- 

 terns and usually pale, many species being white. The periostracum is usually 

 thin and polished. The group may be divided into sections as follows : 



