The Surf Clams. Hen Clams 



Lf. lineata, Say, has a sharply keeled line setting oflf the 

 anterior end, which gapes in a narrow line for the thin foot. The 

 posterior gape is wider. The shell is white and very thin, closely 

 marked with concentric lines. Length, 2 to 3 inches. 



Habitat. — New Jersey southward. 



Genus TRESUS, Gray 



The "Washington Clam (7. NuttalUi, Gray, T. maximus 

 Midd., Schi{othcerus NuttalUi, Conr.) would doubtless, "by any 

 other name" be still the giant of all the surf clams. Like many 

 another of our molluscan giants, it is found on the Pacific coast. 

 Tryon figures this shell as oblong, rounded at both ends. 

 It is remarkable for the wide gape of its white valves at the 

 posterior end, and the narrow gape in front. The body of the shell 

 is much swollen, to accommodate the very large body. The blunt 

 umbones come near meeting over the hinge, which has a deep, 

 wide cartilage pit, and a long channel on each side of the cardinal 

 teeth. A brownish epidermis covers the surface. This mollusk 

 burrows deep in muddy bays. The laborious digger may need a 

 helper to hold on to the clam's "neck" to insure its capture. He 

 finds consolation in the fact that a large chowder may be made 

 of a small number of clams. Dr. R. E. C. Stearns characterises 

 this species as "a noble and estimable clam, which beats any 

 other clam yet discovered for chowder, soup or pies. It has 

 nearly the consistency of an oyster, a very small foot; the pro- 

 portion of tough muscle is less than in Mya arenaria." Length, 

 6 inches. Puget Sound to Southern California. 



Genus SPISULA, Gray 



The Dish Shell (S. catilliformis, Conr.) is a fine large 

 clam, with thin, smooth, white shell covered with a wrinkled, 

 gray, horny epidermis. It has the characteristic Mactra shape, 

 with sub-central, elevated beak. The hinge pit is triangular and 

 very large. The pallial line reaches the middle of the shell. 

 Length, 4 to 5 inches. Vancouver Island to Southern California. 



Hemphill's Surf Clam (5. Hemphillii, Dall) grows even 

 larger than the dish shells. It is a rare species, found at San 

 Pedro and San Diego. A brown epidermis, much wrinkled at 

 the posterior end, covers the white surface. Except for its 



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