OF MASSACHUSETTS. 



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Prismatic structure, 



Prodissoconch, 



Protandric, 



Protoplasm, 



" Seed " scallop, . 



Set, . . . 



Spawning, . 



Spermatozoon, 



Tentacle, 



Testis, 

 Trochosphere, 



Umbo, 

 Valves, 



Veliger, 

 Velum, 



Ventral surface, . 

 Ventricle, . 

 Visceral mass, . 



Shell made up of prisms. 



Small embryonic shell of a mollusk. 



Having male sexual organs while young, and female 

 organs later in life. 



Cell contents life substance. 



A scallop less than one year old. 



Attaching of scallop by byssus. 



To set free the eggs or spermatozoa. 



The male sex cell. 



A more or less elongated process, usually an organ 

 of sense or motion. 



The male gland which produces the spermatozoa. 



Stage in embryonic development, in which the em- 

 bryo is spherical and rotates rapidly. 



The beak or " shoulder " of the bivalve shell. 



Two valves, the right and left, compose the shell 

 of a lamellibranch mollusk. 



Stage in embryonic development in which velum is 

 used as an organ of locomotion. 



A circular pad covered with cilia and used as an 

 organ of locomotion in the early embryonic 



The side opposite the dorsal surface. 

 A chamber of the heart. 



That part of body containing digestive, generative 

 and part of circulatory and nervous systems. 



