The Venus Clams and Carpet Shells 



The Wavy Carpet Shell (7. fludmsa, Gld.) has a thin, pod- 

 like shell, oval, with lamellate, concentric waves vanishing on 

 the sides. A yellow epidermis overlies the white valves. Length 

 scarcely an inch. 



Habitat. — Newfoundland. 



The Ribbed Carpet Shell (7. staminea, (jam.) is obliquely 

 oval, radially ribbed, and brownish, often marked with chevrons 

 of darker shade. It occurs all along the west coast, especially 

 north of San Francisco. It is the "hard-shelled clam" of the 

 markets. Length, 2^ inches. 



The Netted Carpet Shell (7. ZaczWfl/a, Cpr.) is distinguished 

 by the very fine criss-crossing of sharply chiselled lines on its 

 valves. Prickles often stand at the intersections of these lines. 

 The clam-digger takes these to market with the ribbed species; 

 the two betray their hiding-places under the sand by jets of water 

 that spurt up when the siphons are withdrawn by the startled 

 clams. Length, 3 to 4 inches. 



Habitat. — Southern California. 



The Finest Carpet Shell (7, tenerrima, Cpr.) is so finely 

 cancellated as to feel like a file. The shell is large, oval, with 

 small beaks far forward, strong, divergent hinge teeth, and a long 

 external ligament. The mollusk is somewhat rare. It has very 

 long siphons, as the deep pallial sinus on each valve proves. 

 It can go deeper than its kindred. The colour is brownish gray. 

 Length, 5 inches. 



Habitat. — West coast of United States. 



THE ROCK VENUSES 



Genus VENERUPIS, Lam. (RUPELLARIA, Fl. De 



Bellevue) 



Shell bivalve, gaping, elongated; beaks well forward; 

 posterior truncated; surface decorated with concentric, frill-like 

 laminae. Thirty species. Mollusks live in holes in rocks, 

 attached by byssus. They frequent temperate and cold seas. 



The Frilled Rock Venus (V. lamellifera, Conr.) nestles 

 among rocks on northern Pacific beaches. It is white with many 

 thin, papery frills adorning the valve. Usually broader at the 



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