204 OSTEEID^. 



Anomia ephippium. 



Shell rounded, margin irregular; surface scaly, variously wrinkled and undu- 

 lated; beaks pointed, not quite reaching the margin; aperture ovate. 



Ostreum parrum, Lister, Coneh. t. 204, fig. 28. 



Anomia eplnpptnm, Lin. Syst. Nat. 1150. — Gmelin, Syst. 3340, No. 3. — Gualt. Test. 

 t. 97, fig. B.— D'Argenv. Conch, t. 19, fig. C. — Pennant, Brit. Zool. iv. t. 62, 

 fig. 70. — Chemn. Conch, viii. t. 76, figs. 692, 693. —Montagu, Test. Brit. 155.— 

 Wood, Lin. Trans, vi. jtl. 18, figs. 11,12; Inil. pi. 11, fig. 3. — Maton and Rackett, 

 Lin. Trans, viii. 102. — Donovan, Brit. 8h. t. 1, pi. 26. — Born, Mus. fig. 117.— 

 SciiROET. Einl. iii. 383. — Poli, Test. ii. 186, pi. 30, figs. 9, 11. — Da Costa, Brit. 

 Coneh. 165, pi. 11, fig. 3. — Favanne, Coneh. pi. 41, fig. B. — Dillwyn, Cat. i. 

 286, No. 3. — Blai.w. Mai. ]A. 59, fig. 3. — Sowekhv, Gen. figs. 1, 2, 3. — Turton, 

 Brit. Biv. 227; Coneh. ])iet. 2.— Lam. An. sans Vert. vii. 273; Eneyc. Meth. pi. 

 170, figs. 6, 7. — Gould, Livert. 1st ed. 138. — De Kay, N. Y. Moll. 186, pi. 12, 

 fig. 209. — Flem. Brit. An. 395. 



Shell generally rounded, but often produced at one side or at 

 base, so as to assume an oval form ; its margins more or less jagged, 



and its surface scaly from the loose edges of 

 the lines of growth, and variously distorted, 

 undulated, and plaited, according to the ob- 

 jects to which it adheres. Lower valve fiat, 

 -^ ,. ^^=^-^ its aperture ovate, reaching the margin by a 



A. ephippium. l ' o a J 



fissure. Ui)pcr valve slightly convex, little 

 elevated about the beak, which is small, acute, not quite reaching 

 the margin. Substance of the shell pearly, or like talc, of a green- 

 ish tinge, reflecting golden and silvery hues ; within smooth, the 

 muscular impressions opaque Avhite. Usually about an hicli in di- 

 ameter, but growing to three times that size. 



It is found in almndance in oyster-beds, adhering to oysters. At 

 New Bedford it has been found anchored by its muscle to pebbles. 

 Eastport (Cooper^ ; wreck of a frigate, Herring Cove {JVillis). 



This shell varies so much in its form that it is very difficult to 

 characterize it. The most constant trait is the rugged, scaly ex- 

 terior. It not unfrequently assumes a ribbed appearance, in con- 

 sequence of having adhered to valves of Pecteti irradians. 



Anomia aculeata. 



Fig. 90. 



Shell rounded, inclined to be straight at the hinge-margin ; color dingy white; 

 beaks obtuse, terminal; upper valve covered Avith fine, prickly, radiating lines; 

 lower valve smooth ; aperture circular. 



