PATELLA. 



Plate XXI. 



Species 51. (Fig. a, b, c, Mus. Cuming.) 



Patella Bonnaedi. Pat. testa ovatd, subacute convexa, 

 apice subanticd, costis Urisque acute compressis dense 

 radiatd, squamis concentricis decussatd; albd, nicjro 

 velfusco radiatd, intus subpellucido-albd. 



Bonnakd's Limpet. Shell ovate, rather sharply con- 

 vex, siibanterior at the apex, profusely rayed with 

 sharply compressed ribs and ridges, decussated with 

 concentric scales ; white, rayed with black or brown, 

 interior subtransparent white. 



Payraudeau, Cat. Moll, de Corse, p. 89. pi. 3. f. 9-11. 



Hah. Mediterranean. 



A sharply convex sheU, rayed with numerous compressed 

 squamate ribs and ridges ; white rayed with black or rust- 

 brown. 



Species 52. (Mus. Cuming.) 



1'atella Chitonoides. Pat. testd ovatd, aiitice aciimi- 

 natd, valde depressd, crassinsc/dd, irregtilarUer radia- 

 iiid costatd, costis aciitis, rudibus, plus miims obsolete 

 squamato-tuberculatis; inteiise pitrpureo-nigrd, hie illie 

 alho-erosd, intus lacted, inarghie acute denticulato, pur- 

 piireo-niyro. 



The Chiton-like Limpet. SheU ovate, acuminated in 

 ft-ont, very depressed, rather thick, ii'regularly radi- 

 ately ribbed, ribs sharp, rude, more or less obsoletely 



squamately tubercled ; deep purple-black, here and 

 there white-eroded, interior milk-white, margin sharply 

 denticulated, purple-black. 

 Hab. ? 



A very depressed rudely constructed species, strongly 

 rayed with rough irregular bluntly scaled ribs, deep purple- 

 black except where promiscuously white-eroded. 



Species 5-3. (Mus. Cuming.) 



Patella cketacea. Pat. testd ovatd, subdepressd, ra- 

 diatim dense costatd, costis parviusculis, compressis 

 ant tmnidiusculis, obsolete squamatis, valde irregula- 

 ribns ; cretaceo-albd, purpureo-nigro hie illic sparsim 

 maculatd, intns albd, margine denticulato, piirpureo- 

 uigro teime limbato. 



The chalk Limpet. Shell ovate, rather depressed, ra- 

 diately densely ribbed, ribs rather small, compressed 

 or swollen, obsoletely squamate, very irregular ; chalk- 

 white, here and there sparingly blotched with purple- 

 black, interior white, margin denticulated, thinly 

 edged with purple-black. 



Hab. Tahiti. 



Allied to the preceding species, though of a perfectly 

 distinct character, more truly ovate, with the ribs more 

 I numerous and irregular, and less stained with purple- 

 1 black. 



December, 1854. 



