180 



3ory piece of a triangular form, at the summit ; the shell itself, 

 thicker at the anterior end, and very thin and fragile at the 

 posterior end, l-4th to 3-8th of an inch long and so fragile, 

 that the contraction of the animal ruptures them in every 

 direction. In decayed wood at Phillips' Beach, in burrows of 

 eight inches depth, I have found some two and a half inches long, 



Solen. 

 S. ensis. Found on all the beaches in Lynn and Swamp- 

 scott, also nearly opposite the foot of Hardy street, Salem. 



Machsera. 

 M. costata. Plenty on Lynn beaches. 



Solemya. 

 S. velum. Found on the shores of Salem harbor in South 

 Fields, at Beverly Bar, and at Lynn. 

 S. borealis. Found at Lynn and at Chelsea Beach. 



Glycymeris. 

 G. siliqua. Found in stomachs of fish at Swampscott. 



Mya. 

 M. arenaria. Found on all the shores between high and 

 low water mark. It is three or four years old before it is large 

 enough for food. 



Pandora. 

 P. trilineata. Found in a living state at Point Beach, 

 Swampscott, and on shore of Salem Harbor. 

 Osteodesma. 

 0. hyalina. Found in City Mill-Pond in 1840, two years 

 successively ; on the first year they were small and plenty, the 

 next year they were much larger and not so abundant. Found 

 also on Beaches at Lynn. 

 Cochlodesma. 

 C. Leana. Found living, at Point Beach, Swampscott; 

 also, at Chelsea Beach. 



Note. In one of my rambles at Phillips' Beach, I was much aston- 

 ished at some burrows made by Pholas, in the timber of a part of tho 

 wreck of some vessel, that to appearances had laid some years on tho 

 bottom of the ocean, and in a furious storm had been cast on shore ; 

 the burrows were made in the hard oak timber , not in the least state of 

 decay. The Pholas had begun its burrow on the plank outside, and 

 bored through into the timber, diagonally to the grain of the wood. 

 The burrows were about ten inches deep in the timber, their diameter 

 at entrance of timber one inch ; at the other end two and a half inches, 

 as far aa they reached, but the wood was split off, and the shell gone. 



