270 OSTREA. 



can be no doubt that his P.fragilis belongs to this species, 

 and is different from the P.fragilis of Chemnitz, which is 

 considerably narrower in proportion to the length. 



bullata. 50. Shell ovate-oblong, with about thirty- 

 two narrow ribs, and the auricles acute and 

 equal ; hinge transverse. 



Ostrea bullata. Born Mus. p. 1 10. t. 6. f. 8. 



Ostrea inflata. Gmelin, p. 3321. 



Ostrea, No. 21. Schroder Einl. iii. p. 331. 



Pecten bullatus. Chemnitz, vii. p. 348. t. 68. f. 649 h. 



Pecten subauriculatus. Montagu Supp. p. 63. t. 29. f. 2. 

 Inhabits the Mediterranean. Chemnitz. 

 Shell an inch and a quarter long, and but little more than half 



as broad; it is white, and differs from O.fasciata in being 



equilateral, and in having the straight upper margin which 



contains the hinge placed at right angles. 



fragilis. 51. Shell oval-oblong, with about twen- 

 ty-five narrow ribs, and the auricles acute; 

 hinge oblique. 



Ostrea fragilis. Gmelin, p. 3332. 



Ostrea, No. 22. Schroeter Einl. iii. p. 331. 



Pecten fragilis. Chemnitz, vii. p. 349. t. 68. f. 650. 



Inhabits the coasts of the Nicobar Islands. Chemnitz. 



Shell about an inch and a quarter long, and half as broad ; 

 white, brittle, pellucid, and gaping on both sides ; it differs 

 from O.fasciata in being flatter and narrower, and from O. 

 bullata, in having the hinge oblique. The shell which Mr. 

 Montagu mistook for this species he describes to be three- 

 quarters of an inch long, and almost two thirds as broad ; 

 convex, and the ribs marked with intermediate striae ; so that 

 it is probably at most only a trifling variety of O.fasciata. 



hians. 52. Shell oblong, thin, with numerous ob- 

 solete undulated ribs, and transverse striae ; 

 auricles small and acute ; hinge oblique. 



Ostrea hians. Gmelin, p. 3332. 



Ostrea, No. 23. Schroeter Einl. iii. p. 332. t. 9- f- 4. 

 Inhabits the coasts of Norway. Schroeter. 

 Shell an inch and a half long, and half as broad ; gaping at both 



ends, and of a whitish colour; the margin is said to be cre- 



nated on the outside, and very entire within. Schroeter'* 



