PSAMMOBIA. 



Cxenus PSAMMOBIA, Lamarck. 

 Testa transversa, oblmga vel ehngato-ovata, ad latera paulo 

 hians, Icevigata vel concentrice striata, sapissime ince- 

 quilateralis, latere antico rotundato, postico plus minus 

 Jiexiwso-angulato et truHcato, uiterdum pulcherrime 

 sculpto ; colore vario, interdum cum epidermide oUva- 

 ced. Cardo in valvd altera dentibus duobus, plerum- 

 giie bifidis, in altera unico, ligamento externo. Im- 

 pressio miiscularis pallii sinu maximo. 

 Shell transverse, oblong or elongately ovate, a little gap- 

 ing at the sides, smooth or concentrically striated, 

 mostly inequilateral, the anterior side rounded, the 

 posterior more or less flexuously angled and trun- 

 cated, sometimes very beautifully sculptured ; colour 

 various, sometimes with an olive epidermis. Hinge 

 in one valve with two teeth, generally bifid, in the 

 other with one tooth, the ligament being external. 

 Muscular impression of the mantle with a very large 

 sinus. 

 In a recent investigation of the genera ranging in the 

 system between Solen and Tellina, M. Deshayes referred 

 to the Lamarckian genus Fsammobia, a beautiful series of 

 undescvibed species in the collection of Mr. Cuming that 

 had not hitherto found a resting-place, and displaced one 

 or two, as, for example, the Capsa riigosa, that bad been 

 referred to this genus in error. By far the most charac- 

 teristic forms of the group are those which were so de- 

 scribed, and are here for the first time figured. They 

 present a strong generic peculiarity in the flexuous angular 

 development of the posterior angle, which in most species 

 is elaborately sculptured with wrinkled ridges, and are re- 

 markable for their display of delicate colours, generally of 

 ii rosy hue. 



The Psammobia are, with one or two abnormal excep- 

 tions, confined to the Eastern Hemisphere, the genus being 

 well represented on our own shores by the common F. 

 Fcrroensis, and ranging as far south as Tasmania. 



Species 1. (Mus. Cuming.) 

 Psammobia oriens. Fsam. testa ovato-transversd, sub- 

 quadratd, soliduld, inxquilaterali, transversim sub- 

 striatd,in latere postico inaqnaliter sulcata ; carneo- 

 rosed, radiis et lineis angulatis roseo-purpurascentiius 

 notatd, latere antico hreviore, late obtuso, postico ob- 

 lique truncato. 



The kising-scn Psammobia. Shell ovately transverse, 

 somewhat square, rather solid, inequilateral, trans- 

 versely finely striated, unequally grooved on the pos- 

 terior side ; flesh-rose, marked with rose-purple rays 

 and angular lines, anterior side shorter, broadly ob- 

 tuse, posterior obliquely truncated. 



Deshayes, Pro. Zool. Soc. 1854, p. 318. 



Hab. Japan. 



Of the same typical character as F. maxima, more equi- 



valve and square-built, delicately rayed, and elegantly 



mottled with violet triangular marks. 



Species 2. (Mus. Cuming.) 



Psammobia puella. Fsam. testa elongato-iransversd, 

 tenui, depressd, inaquilaterali, transversim striata, 

 striis in latere jMstico rugmformibus ; nitente-albd, au- 

 rantio-rufo pallide radiatd, umbonibus nitente-viola- 

 ceis; latere antico longiore, rotundato, postico brevi, 

 obtuse angulato. 



The tender Psammobia. Shell elongately transverse, 

 thin, depressed, inequilateral, transversely striated, 

 stria; on the posterior side wrinkle-like; shining 

 white, faintly rayed with orange-red, umboes shining 

 violet; anterior side the longer, rounded, posterior 

 short, obtusely angled. 



Deshayes, Pro. Zool. Soc. 1854, p. 320. 



Hab. Australia. 



Bluish-white, shining, faintly rayed with orange-red, 



neatly sculptured on each side with raised stria;. 



3. (Mus. Cuming.) 

 Psammobia modesta. Fsam. testa elongato-transversd, 

 convexiusculd, subaquilaterali, medio substriatd; al- 

 bidd, pallide ru/escente sparsim radiatd; latere antico 

 rotundato, postico subangulato. 

 The modest Psammobia. Shell elongately transverse, 

 rather convex, neariy equilateral, faintly striated in 

 the middle ; whitish, sparsely rayed with faint red ; 

 anterior side rounded, posterior slightly angulated. 

 Deshayes, Pro. Zool. Soc. 1854, p. 319. 

 Hab. Australia. 



More convex and less angularly formed than the pre- 

 ceding species. 



June, 185 



