The Venus Clams and Carpet Shells 



olive ground. Over the smooth, white shell substance is laid a 

 shiny epidermis, like a coat of lacquer. It is brittle and, scaling 

 off, removes all the colour. Length, 2 to 4 inches. 



Habitat. — Japan Sea to Indian Ocean. 



The Convex Cytherea (C. convexa, Say) is a smooth little 

 round clam, with a convexity behind its prominent beaks. Length, 

 2 inches. 



Habitat. — Nova Scotia to Cape Hatteras, west coast of 

 Florida. 



Sub-genus CALLISTA, Morch 



The Giant Callista (C. gigantea, Gmel.) is shaped and painted 

 like, a sunset shell, but the plaid pattern is oftenest developed in 

 dull blue, lilac or gray, on a pale ground. A brown band of some 

 width is set a little back from the margin. The hinge is nearer 

 the anterior end. The posterior end is elongated, and pointed 

 to a slight degree. The china-like shell is covered with a livid or 

 pink epidermis. This species is especially abundant on the beaches 

 of western Florida. Length, 5 to 6 inches ; width, 3 inches. 



Habitat. — Cape Hatteras to Texas. 



The Spotted Callista (C. maculata, Linn.) is oval, ventricose, 

 with a shiny surface, fawn-coloured, with broken radiating bands 

 of violet-brown, and chevron prints in the spaces between the 

 bands. A horny epidermis covers the shell. The flesh is edible 

 as is also the giant Callista's, but both have a peppery taste one 

 must learn to like. Length, 4 inches; width, 3 inches. 



Habitat. — Cape Hatteras to Texas. 



Sub-genus TIVELA, Link. 



The Thick-shelled Tivela (C crassatelloides, Conr.) is one 

 of the finest, as well as largest, of California clams. Walk along 

 the beach at ebb tide, and you may see a depression like a thumb 

 print, deep in the sand. Dig a few inches with a convenient 

 shell scoop, and you reach the great three-angled clam, which 

 reminds you of the surf clam, Mactra solidissima, of the east 

 coast. The thick valves are scored with growth lines, yellowish 

 but painted with streaks or rays of purple and hints of red. 

 The lips of the valves are thick and rounded. A single clam 

 often weighs a pound. 



I have never found these mollusks as abundant as I wished. 



349 



