127 



T. PSITTACEA. Lam. \2.Turt. J?.^.236. F. p. 

 368. ANOMIA P. Gmel. 3248. Ch. f. 713. D. p. 

 296. Turt. D. p. 5.f. 42,3,4. Oval convex, blackish 

 horn-color, inflected and smooth at the sides, longitudi- 

 nally striated on the disc ; beak of the upper valve elon- 

 gated, curved and pointed. 1. Trignmouth, excessively 

 rare. 



T. AURITA. Flem. Phil. Zool. 2. p. 498. t. 4./. 5. 

 F. p. 369. T. COSTATA. Lowe. Zool. J. 2. p. 105. t. 

 5./. 8,9. Desk. inLam.l.p. 351. Regularly ribbed, 

 the eight ribs on the disc the most distinct and rounded, 

 obsoletely wrinkled concentrically, the lateral ribs 

 indistinct; the larger valve broadest in the middle, 

 semicircular at the margin and narrowed at the apex ; 

 small valve suborbicular; the hinge margin subtrun- 

 cated or rather obtusely angular and having the sides 

 depressed ; inner surface punctated. 0,20.... 0,30. 

 W. Scotland.' 



CLASS. MOLLUSCA. 

 ORDER. GASTEROPODA. 

 TRIBE. PHYLLIDIAN^. 



GENUS. CHITON. 



Shell consisting of eight imbricated testaceous plates, 

 connected by a more or less coriaceous margin. 



