MARINE AQUARIA 



found on the sandy beaches on the Atlantic coast from Labrador to Cape 

 Hatteras. 



Petricola fholadiformis, (Lam,), or Boring Clam, has elongated, acutely 

 rounded, chalky, i J^ inches long valves, the anterior part short and the 

 posterior long and neatly rounded. The animal has two long siphon 

 tubes united at the base, with the inhaling tube the longer. Found in 

 varying localities along the Atlantic coast at low-water marks. 



Jcra transversa, (Say), or Common Cockle, has rhomboidal, oblong 

 I yi inches long valves, with 32 to 35 ridges or ribs placed in radiating lines 

 from the umbones to the margins. This is the common radiate-shelled 

 clam of the Atlantic coast. 



Venus mercinaria, (Linn.), or Common Hard-shell Clam, Quahog, 

 has thick and solid, obliquely ovate or heart-shaped grey and chalky valves 

 with the anterior ends very short, the posterior ends terminating in a blunt 

 truncated point, and the curved and elevated umbones placed far forward 

 to project nearly to the front of the shell. This clam is brought into the 

 market under different names, the younger as the Cherry Stone and Little- 

 neck, the older as the Hardshell, and the very large ones, which reach a 

 length o( 2j4 to 4 inches, as the Chowder Clam. Those having shells 6 

 inches long or larger are known as Horse or Sea Clams. Common along 

 the entire Eastern and Middle States Coast. 



Mytilus edulis (Linn.), or Edible Mussel, has thin, polished, triangu- 

 lar-ovate, dark-bluish, 25^ inches long valves, with a pointed beak and 

 plainly defined lines of growth. The umbones are immediately at the 

 beak. Very common between tide-marks on the Atlantic coast, from the 

 Arctics to North Carolina. 



Modiolus plicatulus, (Lam.), or Horse Mussel, has oblong-ovate 

 much elongated greenish-brown and horn-colored 2 to 3 inches long 

 valves ; with the posterior end traversed by numerous radiating ribs. The 

 umbones are placed above the beak. Common on muddy banks of estu- 

 aries and shores, crowded in vast numbers, exposed at low tide ; from 

 Nova Scotia to Georgia. 



Pecten gihbus, var. irradians, (Lam.), or Common Scallop, has nearly 

 round, rather strong, dusky or blackish 1)4 inches long valves, having 

 about 20 elevated, rounded ribs, wrinkled concentrically by fine lines of 

 growth, and an ear-like hinge about two-thirds as broad as the shell. 

 Common along almost the entire Atlantic coast from Nova Scotia to 

 Tampa, Fla. 



Ostria virginica, (Gmel.), or Chesapeake Bay Oyster, has now be- 

 come a widely distributed native species, found along the entire Atlantic 

 coast. Owing to its sedentary life, it has become very irregular in both 



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