History of British animals - University of Guam Marine Laboratory

AsfAitxE. MOLLUSCA. PSAMMOBIAD^E. 439497. P. polygona.— Subovate, with transverse and minutelongitudinal striae ; retral extremity angular, and undulate atthe margin.Tellina pol. Mont. Test. Brit. Sup. 27. t. xxviii. f. 4—P. pol. Turt. Biv.Brit. 96.—Frith of Forth Mr Laskey.Length half an inch, breadth a little more ; whitish ; anteally rounded ;teeth, in one valve, two, large and distinct ;in the other a large triangularbifid tooth, with an approximate small one."- 498. P. strigillatus.— Oblong, striate in two directions on theanteal side, with one of the teeth oblique and laminar.Chama angusta, List. Conch, t. ccccxvi.— P. stri. Turt. Biv. Brit. 97« t; vi.f. 13 Torbay and Cornwall.Length an inch, breadth 2 inches ; narrower at the retral side ; yellowishwhite; ventral margin straight ; about 30 longitudinal striae.499. P- scopula.— Kidney-shaped; striate in two directionson the l'etral side, with all the teeth erect.Turt. Biv. Brit. 98. t. G. f. 11, 12. Exmouth.Length three-eighths, breadth six-eighths ; glossy white It is distinguishedfrom the last by the sides being more open where the valves are alittle reflected ; in the middle there is an evident contraction ; the oblique.striae are not more than 20, the beaks are more prominent, and the teeth areall erect, and close together.EXTINCT SPECIES.L P. solida.— Transversely elongated, depressed, tumid, nearly smooth,slightly curved ;an obtuse carina marks the retral side.—Sower. Min. Conch,t. 342.— Upper marine formation, Headon Hill.Gen. CXXIII. ASTARTE.— Suborbicular or transverse;subinequilateral ; hinge with two diverging teeth ; a depressionbefore the beaks ;impression of the cloak entire,—exhibiting no syphon cicatrix. This genus, instituted bySowerby (Min. Conch, ii.85.),is identical with the subsequentlyannounced Crassina of Lamarck.* Margm crenulated.500. A. sulcata.— Shell suborbicular, flattish, with broad,concentric furrows, obsolete towards the beaks and sides.Venus sulcata, Mont. Test. Brit. 131.— England, and north of Scotland.Diameter about seven-eighths of an inch ; white, with an opake brown cuticle; strong and thick ; beaks prominent, inclining, under which is a lanceolatedepression ; cartilage side likewise depressed, but narrower, exteriormargin rounded ; inside white, smooth and glossy at the margin, the middledull and rough;edge crenulated ; hinge with three teeth in one valve, themiddle one larger than the others, with a deep cavity in one valve, into whichthe two teeth of the other valve lock. Montagu states his having receivedthis shell as English from Mr Sowerby, and that according to Mr Swainson,