7 + 



CHAPTER XVII. 



OF THE OSTREA. GENUS XIV. 



ST RE A. 



"Animal a 7\'thj/s. Shell bivalve inequivalved, somewhat eared; hinge 

 without teeth, with a little ovate hollow and lateral transverse stria." — 

 Linn. 



LiNN^us makes four divisions of this genus, which indudes 

 both Scallops and Oysters. The first division consists of 

 Scallops with the ears on each side, the beaks equal ; the 

 second division contains those that have one ear fringed as it 

 were with spines, and generally unequal ; the third has the shell 

 on one side of the beaks more gibbous or swelled larger than 

 the other ; and the fourth consists of rough ones, or those com- 

 monly called Oysters. 



The Scallops or Pecteus have at the hinge a small hollow, 

 nearly ovate or somewhat triangular, under the beaks in each 

 valve, which hold the connecting cartilage (^pL 4. /. 41. a), 

 but have no teeth ; the cartilage of course is internal ; there 

 is on both sides of the beaks in each valve a somewhat trian- 

 gular appendage or extension of the shell, called an ear (/)/. 4. 

 /. 41. bby. In some species, as Ostrea maxima, Jacobea, &c., 

 the ears on each side the beaks are nearly equal : these are 

 placed in the first division. In some, as Ostrea varia, Pallium, 

 &c., the ears on one side the beak in each valve are much 



