The Surf Clams. Hen Clams 



are counted men, pigs, star fishes and whelks. Length, 7 

 inches. 



The Beaked Surf Clam (M.nasuta.Gld.) is regularly elHpti- 

 cal, with a somewhat elevated beak on each side of the central 

 hinge, and thin white valves. Length, 3 to 4 inches. 



Habitat. — California. 



The Californian Surf Clam (M. Californica, Conr.) looks 

 Hke a Httle Mya, being thin-shelled, and flattened behind 

 the central, furrowed beaks. Over the white surface is a 

 yellow epidermis. Beaks very small, close. Length, 2 to 3 inches. 



The Mattock Surf Clam (M. dolabriformis, Conr.) has the 

 form of an axe head, and is thin, flat, and white. Length, 3 inches. 



Habitat. — San Diego southward. 



M. lateralis, Say, is triangular and swollen, with a wavy 

 and bluntly ridged posterior surface, and a ridge to balance it 

 near the front. The prominent beaks are nearly central. Length, 



1 inch. 



Habitat. — Atlantic coast. 



M. fragilis, Chemn., is a delicate shell recognisable by the 

 darker colour of the epidermis covering the posterior area, which 

 is set off by distinct ridges. Elsewhere the epidermis is yellowish. 

 Faint rays extend from the central compressed umbones to the 

 wrinkled margins opposite. Lining white, polished. Length, 

 3 to 4 inches. 



Habitat. — North Carolina southward. 



Genus LABIOSA, Schmidt 



Shell oblong, thin, widely gaping and reflected posteriorly; 

 hind margin defined by a thick lip or keel. 



Sub-genus Rseta is a small group of surf clams with widely 

 gaping, thick-lipped valves. A sharp ridge defines the posterior 

 area. The valves are almost heart-shaped,thin, with concentric 

 folds on the surface. 



The Channeled Raeta (L. canaliculata. Say) has the char- 

 acteristics above — it is the type. The grooves cut deep, making 

 a very fragile shell; though much swollen in the front half, it 

 becomes suddenly flattened behind. Interior grooved. Length, 



2 to 3 inches; width, somewhat less. 



Habitat. — New Jersey southward. 



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