BIVALVES OSTREA. 37 



111 the Ostrea Imbricata and Dubia. In others again tlie 

 striae are crenate, as in the Ostrea Radula; and some, 

 as tlie Ostrea Nodosa, &c. have large knobs or tubercles 

 raised n[)on the ribs. The margins of the interior of the 

 OstresD iirc mostly crenate or toothed, and are often beau- 

 tifully colort d. 



The hinge is universally without teeth, and is furnish- 

 ed with an ovate hollow ; in the vicinity of which are 

 placed lateral transverse grooves, which run in a parallel 

 direction in each valve, but do not lock into each other, 

 as in the genus Area. This division of the Ostreae, viz. 

 the Scallops, have the faculty of leaping out of the water, 

 even to the height of half-a-yard, or more; and, opening 

 their shells, they eject the water contained within them; 

 after which, sinking underwater, they suddenly close their 

 shells with a loud snap. 



The common Scallop, Ostrea Maxjima, is found in-most 

 European seas, in large beds, from which they are dredged- 

 upby the fishermen, and afterwards pickled and barrelled 

 for sale ; in some instances also they are brought to market 

 in the state they are caught, and are eaten fresh. 



These shells were formerly worn by pilgrims, on their 

 hat or coat, as a mark of their having crossed the sea, for 

 the purpose of paying their devotions at the holy shrine 

 in Palestine: in commemoration of which, they are still 

 preserved in the armorial bearings of many families of 

 distinction. Scallops delight in harbouring among fuci 

 and zoophites. 



The second class or division of Ostrete consists of those 

 which in construction, substance, and coloring, are more 

 nearly allied to that sort of shell so universally known by 

 the name of the common or eatable Oyster. The species 

 of this division are mostly of a much more irregular form 



