PECTEN. 



Plate XII. 



Species 45. (Mus. Cuming.) 



Pecten bifrons. Tect. testa trigono-orhiculari, cequila- 

 terali, vix aqnivalvi; valvd dnistrd convexd, cost is par- 

 vis septem ad ocfo lirisque numerosis lineai-ibus radiatd, 

 interstitiis minute yranulatis, violascente, costis lirisque 

 l/svibus, intense violaceis ; valvd dextrd planiore, ecos- 

 iatd, liris radiatd, interstitiis undique minute graimla- 

 tis ; auriculis suhcequalihus. 



The two-faced Pecten. Shell triangularly orbicular, 

 equilateral, scarcely equivalve; left valve convex, rayed 

 with seven to eight small ribs, and numerous linear 

 ridges, interstices minutely granulated, violet, ribs 

 and ridges smooth, deep violet ; right valve flatter, 

 not ribbed, rayed with ridges, the interstices being 

 minutely granulated throughout ; ears nearly equal. 



Lamarck, Anim. sans vert. (Deshayes' edit.) vol.vii. p. 131. 



Hah. Port Adelaide, South Australia. 



The surface of this species, save on the ribs and ridges, 

 is of a peculiar bloom-coloured granular shagreen character. 



Species 46. (Fig. a, b, Mus. Cuming.) 



Pecten serratus. Pect. testd ovatd, paiilo altiore quam 

 longd, tenui, compressd, inaquilaterali ; auriculis valde 

 huBqualibus ; inaquivalvi, valvd dextrd paulo convex- 

 iore, valvis ambabus radiatim costatis et tenuiliratis, 

 costis ad decern, superjiciariis, interdum fere obsoletis, 

 squamatis, squamis subdistantihus ; ceerulescente-cine- 

 red, vel intense cocciued, lineis tenuibus albis promiscue 

 decussatd, costis palUdioribus. 



The serrated Pecten. Shell ovate, a little higher thaa 



long, thin, compressed, inequilateral ; ears very un- 

 equal ; inequivalve, right valve a little more convex, 

 both valves radiately ribbed and finely ridged, ribs 

 about ten in number, superficial, sometimes almost 

 obsolete, squamate, scales rather distant ; bluish-ash, 

 or deep scarlet, promiscuously decussated with fine 

 white lines ; ribs paler. 



SowERBY, Thesaurus Conch, vol. i. p. 69. pi. 13. f. 56. 



Hab. Philippine Islands. 



A very characteristic species, various in ground-colour, 

 but curiously cross-laced with very delicate white Unes. 



Species 47. (Mus. Cuming.) 



Pecten Japonicus. Pect. testd orbiculari, compressd, 

 utrinque kiante, subcequilaterali, cequivalvi; valvis extus 

 lavibus aut tenuissime concentrice striatis,fu.sco-rubente, 

 intus liris angustis binis quatuor vel sex et quadraginta 

 radiatd, alba, prope marginem lutescente ; auriculis 

 parvis, csqualibus. 



The Japan Pecten. Shell orbicular, compressed, gaping 

 on each side, nearly equilateral, equivalve ; valves 

 outside smooth or very finely concentrically striated, 

 brown-red, inside rayed with from forty-four to forty- 

 six narrow ridges, arranged two and two, white, yel- 

 lowish near the margin ; ears smaD, equal. 



Ostrea Japonica, Gmebu, Syst. Nat. p. 3317. 

 Pecten Japonicus, Lamarck. 



Hab. Japan, China. 



Closely allied to P. pleuronectes, but of larger and firmer 

 growth, and not rayed in the painting. 



December, 1852. 



