WORMS. TESTACEA. 66. Oftrea. 257 
Nummaria; Shell roundifh, fmooth, flightly eared and tranfverfely ftriate. . 
Inhabits the Mediterranean ; fize of a man’s nail. 
Shell polifhed, with undulate rufous marks: the ftriz very fine, 
#Nucleus. Shell obliquely ovate, fmoothifh, with a triangular hinge. 
Pennant Brit. Zool: iv. tab, 58. fig. 59. 
Barbut, tab. 7, fg. 6. Gualet. test. t, 88. R. 
Chemn. conch, 7. tab. 58. fig, 574. a, b. 
Inhabits European feas, and is fometimes found foffile: fize of 
an hazel nut; covered with an olivacéous skin under which it 
is white, within filvery : /he// unequally triangular, with very 
fine perpendicular ftris croffed by a few arched traníverfe 
ones: depreffion behind the beaks heart-fhaped. 
Rhomboidea Shell entirely white, rhomboid heart-fhaped and ribbed, 
the anterior and dorfal ribs knotty: beaks femote. ^ 
Lister. 140. 244. fig. 75. Gualt- teft. 1,87, As 
Knorr Vergn. 4. tab. 14. figs 2. 
Chemn, conch. 7. tab. 56. fig-553, a, b. ; 
Inhabits the /ndian and American Ocean; anterior flope heart- 
. fhaped, pofterior one rhomboid, 
Marmorata: Shell equilateral, thin, flattith, with very fine decuffate 
ftri: : beaks approximate: hinge arched. 
Chemn. conch. 7. tab. 57. fig. $63. 
Inhabits the American Ocean :: white varied with yellowifh cha- 
ractere and fpots. 
Angulofa, Shell ventricofe, with longitudinal ftriz and lines, and an- 
gular on one fide: beaks approximate: hinge arched. 
Lister conch, tab. 245. fig. 76. 
Chemn. conch. 7. tab. 57. fig. 567. 
Inhabiss fhores of Africa and American Oceak: brown with 2 
few fpots. 
Scapha. Shell oblong, very much depreffcd, ftriate: beaks very 
flightly prominent. — 
Inhabits Ceylon. Gronov. Zooph. tab. 18. f. 7: 
66. OSTREA. Animal a Tethys: _/hell bi- 
valve, generally with unequal valves and 
flightly eared: hinge without teeth, but 
furnifhed with an ovate hollow, and moft- 
ly lateral tranfverfe grooves. Oyfter. 
P METUS NN queo EUR E : Moft 
