0ST11EA. 249 



zic-zac. 3. Shell with about twenty depressed ribs; 

 lower valve convex, and the upper flat. 



Ostrea Zic-zac. Linneeus Syst. Nat. p. 1 144. Bruguiere 



Enc. Meth. p. 98. Schroder Einl. iii. p. 300. Gmelin, 



p. 3316. 

 Pecten Zic-zac. Chemnitz, vii. p. 277- t.6l. f. 590 to 592. 

 Lister Conch, t. 168. f. 5. Fetiver Gaz. t. 153. f. 7. 



Knorr, ii. t. 19- f. S, and t. 20. f. 1. Regenfuss, i. t. 11. 



f. 53. Favanne, t. 55. f. B. Enc. Meth. t. 207. f. 1. 

 Variety. With the upper valve slightly convex. 

 Ostrea Laurentii. Gmelin, p. 3317. 

 Ostrea, No. 1. Schroeter Einl. iii. p. 322. 

 Pallium Lorenziana. Chemnitz, vii. p. 282. t. 6l. f. 593 



and 594. 

 Favanne, t. 55. f. E 3. ? 

 Inhabits the coasts of Jamaica. Lister. West Indies and Pro- 

 vidence. Humphreys. Red Sea. Forskael. 

 Shell about two inches and three quarters long, and three inches 

 broad ; of a brown or chestnut colour, and frequently pret- 

 tily variegated with yellow or white ; the ribs on the flat valve 

 are longitudinally divided, and appear twice as numerous as 

 on that which is concave. O. Laurentii is a native of the 

 South Seas, and Kaemmerer says it is only a variety of this 

 species. 



striatula. 4. Shell with sixteen rays, and trans- 

 verse membranaceous striae ; margin very en- 

 tire. 



Ostrea striatula. Linnaus Syst. Nat. p. 1144. Gmelin, 

 p. 3316. 

 Inhabits the Indian Ocean. Linnaeus. 

 Linnaeus has described this species to be of the middle size, with 



the lower valve but a little more convex than the upper ; 



colour purple, variegated with white, and the interstices of 



the rays white ; inside yellowish. 



minuta. 5. Shell with about twenty convex rays, 

 and the valves unequal. 



Ostrea minuta. Linnaits Syst. Nat. p. 1 144. Gmelin, p. 

 3317. - . .. 



Inhabits the Indian Ocean. Linnaus. 

 Shell rather small, with the lower valve white and very convex, 



and the upper valve flatter, plaited, and clouded with brown. 



