SNAILS AND MUSSELS 



Found in creeks and small rivers on muddy bottoms in 

 shallow water, sometimes in sand. A common mussel on the 

 Atlantic slope to Georgia. 



Fig. 265. — Paper-shell mussel, Anodonta cataracta: 

 I, left valve; 2, shell, showing beaks and hinge. 



Paper-shells, Anodonta. — The shells are thin, generally 

 smooth and shining, often winged posteriorly (Fig. 265). • The 

 outer surface is greenish or brown and is often marked by light 

 and dark concentric bands indicating rest periods in growth 

 (P- 317); the lining is dull white or pinkish. The breeding 

 season is in late summer. When full the brood pouch of the 

 outer gill looks like a thick brown pad. The glochidia can 

 be found in the pouches through October and often into mid- 

 winter; each shell bears a hook. Length of adult about 4 

 inches. 



Found in clear running streams, also in lakes. Common on 

 the Atlantic slope, south to South Carolina. 



Finger-nail clams, Family Sphaeridae. — Few of these small 

 white mussels or "finger-nail clams" are more than half an 

 inch long; SphcBrium sulcahun (Fig. 266), one of the largest of 

 the family, measures three-quarters. The shells are thin, 

 usually white, or yellowish, and the lining is dull white. The 

 form of the animals is similar to that of the larger mussels but 



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