The Surf Clams. Hen Clams 



narrower anterior end and shallower pallial sinus, this might be 

 mistaken for the preceding species. Length, 6 inches. 



THE OTTER SHELLS 

 Genus LUTRARIA, Lam. 



Shell oblong, gaping at both ends; cartilage plate prominent, 

 triangular, with one or two small teeth anterior to it; pallial sinus 

 deep, to accommodate the long, united, leathery coated siphon. 

 Mantle closed e cept at opening for the protrusion of the strong 

 foot; gills taper to mouth. Thirty-three species, living in sandy 

 mud of quiet bays and in estuaries of rivers, burrowing vertically 

 like My a. 



The Oblong Otter Shell (L. ohlonga, Gmel ) has the out- 

 line of a Hollander's wooden shoe, the beak at the ankle, the 

 broad posterior end for the toe. Out of this the great siphon pro- 

 trudes upward to clear water, while the foot ranges fifteen inches 

 or more below in the sandy mud. The hinge is like a pivot and 

 works in two planes: without parting the ventral lips of the shell 

 the gape at either end may be closed. The foot extends out 

 through the anterior end. The long side of the body is covered 

 with a closed mantle. 



Certain Channel Islanders laboriously dig these clams in 

 shallow water, and use them for food. As shell fish they are 

 known as "clumps." The shells are often five inches long. 



Habitat. — Northern Europe. 



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