ARCA. 239 



Inhabits the coasts of Bengal. Lister. America. Linnaus. 

 Red Sea. Forskaeh South Seas. Humphreys. Antilles. 

 Brnguiere. 



Shell about an inch and a half in diameter, thick, rather pon- 

 derous, and has from sixteen to twenty broad strong longi- 

 tudinal ribs ; the margins of both the slopes are protuber- 

 ant by the hinge, and this gives the shell some slight appear- 

 ance of being eared ; the colour is white, marked with irre- 

 gular interrupted transverse bands, or spotted with reddish 

 brown ; the inside is white, more or less spotted with brown 

 towards the margin. 



pectinata. 30. Shell orbicular, with smooth longi- 

 tudinal crowded ribs ; margin crenated. 

 Area pectinata. Gmelin, p. 3313. 

 Area pectunculus minor. Chemnitz, vii. p. 238. t. 58. f. 



571 and 572. 

 Area pectunculus, Var. Bruguiere Enc. Meth. p. 111. 

 Area, No. 19. Schroeter Einl. iii. p. 287. 

 Lister Conch, t. 243. f. 74. Favanne, t. 53. f. D 7. Enc. 

 Meth. t. 311. f. 6. 

 Inhabits the coasts of Barbadoes. Lister. West Indies. Chem- 

 nitz. 

 Shell commonly about three-quarters of an inch in diameter, 

 white, and irregularly marked with pale brown or yellowish 

 spots ; it differs from A. pectunculus, not only in its smaller 

 size, but also in having the longitudinal ribs much more 

 crowded and numerous. 



decussata. 31. Shell orbicular, with decussated 

 stria? ; apices approximated, and the margin 

 crenated. 



Area decussata. Linncsus Syst Nat. p. 1142. Chemnitz, 



vii. p. 226. t. 57. f. 56 1. Schroeter Einl. iii. p. 270. 



Gmelin, p. 3310. Bruguiere Enc. Meth. p. 1 12. 



Kttorr, v. t. 30. f. 3. Regenfuss, i. t. 2. f. 22. Enc. Meth. 



t. 311. f. 1. 



Inhabits the Indies. Linnceus. Coasts of the Danish Island 



of St. Thomas. Chemnitz. 

 Shell about seventeen Hues long, and eighteen broad ; white, 

 with reddish brown oblong spots, which sometimes form ir- 

 regular transverse bands ; it is indistinctly marked with about 

 fifty-four obsolete very slightly elevated ribs, and the decus- 

 sated stria? are so fine as to be hardly discoverable without 

 - the assistance of a glass. 



