PANDORA.— Plate I. 



red, linear grooves ; left valve very convex, rayed 

 anteriorly with a flexuous, lightly depressed 

 groove. 



Carpenter. Proc. Zool. Soc. 1850. 



Hab. California. 



In our common British species, the deep valve gives 



\QTy slight indications of a sort of flexuous depression 



like that which is fully developed in the present species. 



Species 4. (Mus. Brit.) 



Pandora elonc.ata. Pan. testa tenuissimd, compressa, 

 valde amuitd ; latere antico brevissimo, antjiisto, 

 obli/jii' cLnitit ,- hitere postico lato, margine ventiali 

 c >ni-:M'i.<siiii'i: iiiiirijiiie dorsali. crescentiformi; rostro 

 aiKjiistit, pri'ihirtn ; costii dorsuU tumidd ; valvd 

 sinistra planiiiscuhi. 



The elongated Pandora. Shell very thin, com- 

 pressed, much arched ; anterior side very short, 

 narrow, obliquely elevated ; posterior side broad, 

 ventral margin very convex ; dorsal margin 

 crescent-shaped ; beak narrow, produced ; dorsal 

 rib tumid ; left valve rather flat. 



Carpenter ? MS. Mus. Brit. 



n„b. — ? 



The peculiarity of this shell is the oblique narrowing 

 of the anterior side and deepening of the ventral margin 

 on the posterior. 



Species 5. (Mus. Brit.) 



Pandora oblonga. Fan. testd tenui, attenuata, rectius- 

 culd, latero antico angustiusculo ; latere postico 

 elongate, versiis 7-ostrum attenuate ; rostro truncate ; 

 valvd sinistra moderate convexd ; dente in valvd 

 plannlatd ligamentoque minimis. 



The oblong Pandora. Shell thin, attenuated, rather 

 straight, anterior side rather narrow ; posterior 

 side elongated, attenuated towards the beak ; beak 

 truncated ; left valve moderately convex ; tooth in 

 lower valve and ligament very small. 



SowERBY. Species Conchyliorum, Pt. I. Pandora Sp. 

 f. 10. 



Ilab. Kiver Gambroon. 



This species diff'ors from Pandora inaqiiiralvis in its 



length and narrowness. The tooth and ligament are 



also very small. 



Species G. (Mus. Brit.) 

 Pandora trilineata. Pan. testd conqjressd, altiiisculd 



distanter rugatd, crassiusauld ; margine dorsali 

 panld depresse-arcuato, rostro obtusissime, truncate ; 

 costd dorsali acuatd, subnedosd; valvd dcxtrd ad 

 marginem ventralem valvam sinistram supcranti ; 

 valvd sinistra planiusculd. 



The trilinear Pandora. Shell compressed, rather 

 elevated, distantly wrinkled, rather thick ; dorsal 

 margin a little depressed in a curve, beak very 

 obtuse, truncated ; dorsal rib sharp, rather nodose ; 

 right valve overlapping left valve at the ventral 

 margin ; left valve rather flat. 



Sat. Adams, Proc. Zool. 



Hab. Ceylon. 



More solid and pearly than either of tiie British 

 species. 



Species 7. (Mus. Sowerby-) 

 Pandora oltusa. Pan. testa ovatd, rectiiisciild, tenui, 



latere antico In-evi, angulate, supcrne cuneate ; 



latere postico expauso, truncato, margine dorsali vix 



depresse ; costd dorsali inconspicud ; valvd sinistra 



convexd, versiis umbunes rugatd. 

 The obtuse Pandora. Shell ovate, rather straight, 



thin, anterior side short, narrow, cuneate above ; 



posterior .side expanded, truncated, dorsal margin 



very little depressed ; dorjal rib inconspicuous ; 



left valve convex, wrinkled towards the umboes. 

 Le.^ch. MS. Brit. Mus. 

 Mytilus ])inna, Pennant. 

 Anatina truncata, Turton. 

 Hab. South-west coast of Encland. 



Species «. (ilus. Brit.) 



Pandora arcuata. Pan. testd altiiisculd, dolabriforiui, 

 latere antico subproducto, margine rotnndu ; lattre 

 postico eleganter arcuate ; rostro p)roducto, elevate ; 

 valvd, sinistrd intlts medio et versus umbones 

 costellis margaritaceis radiatd. 



The arched P.andora. Shell rather elevated, hatchet- 

 shaped, anterior side rather produced ; margin 

 rounded : posterior side elegantly arched, beak 

 produced, elevated ; left valve rayed inside, in the 

 middle and near the umboes with pearly riblets. 



Sowerby. Species Conchyliorum, Med. PI. f. 27, '2ii. 



Hab. ? 



There is a peculiar radiation of pearly stria? in the 



interior of this shell, which is rather distinctly beaked 



and gracefully curved. 



