58 BIVALVES. 0STRE4. 



C. Hinge with a perpendicular grooved line. 

 Perna {Oblong O.) Legumeii. 



Isognomon {Rudder O.) Alata. 

 Ephippium {Saddle O.) Mytiloides. 

 Picta. Torta. 



Pes-lutrae. 



ANOMIA. — Anomia or Antique Lamp. 



Animal — an emarginated^ ciliated, strap-shaped body; with 

 bristles or fringe affixed to the upper valve ; arms two, 

 linear, longer than the body ; connivent projecting, al- 

 ternate on the valve, and ciliate on each side, the fringe 

 affixed to each valve : shell bivalve, inequivalve, one of 

 the valves fiattish, the other gibbous at the base, with a 

 produced beak, generally curved over the hinge: one of 

 the valves often perforated near the base: hinge with a 

 linear, prominent cicatrix, and a lateral tooth placed 

 within, but in the flat valve, on the very margin: two 

 bony rays for the base of the animal. 



Of this curious genus of Bivalves, there are fifty- one spe- 

 cies described ; however, several out of that number have 

 hitherto only been found in a fossil or petrified state. 



Those which are recent, or found alive in the sea, arc 

 frequently rare and valuable. The shells are usually in- 

 equivalve, one of them often fiattish, the other gibbous at 

 the base, terminating in a produced beak, which curves 

 upwards over the hinge, and frequently has a small per- 

 foration in it, near the base: through which the, animal 



