118 TESTACEOUS MOLLUSCA. 



subradiatingly painted with brown ; posterior side the shorter, but 

 somewhat produced ; anterior side rather sloping ; margins de- 

 pressed ; with concentric ribs which are lamellar anteriorly, obtuse 

 and broadish centrally, sublamellar posteriorly : umbones rather 

 prominent; ventral margin rounded, denticulated within. 1^... 

 1-J. — Peru. 



V. Australis. Sow. Z. P. 1835. Ovate, subtriangular, 

 thickish, somewhat tawny, with sub radiating subtriangular spots ; 

 with elegant crowded thin concentric ridges, which are obtuse, more 

 elevated near the sides and radiatingly decussated ; dorsal edge rather 

 elevated, ventral rounded and denticulated within. T 9 ^ . . l-^. — 

 Swan River. 



V. Costellata. Sow. Z. P. 1835. Obovate, brownish, some- 

 times prettily dotted at the apices, turgid, with concentric reflected 

 lamellar riblike striag, which are more prominent on the anterior 

 side, and are decussated by impressed radiating white lines : lunule 

 distinct and heart shaped, its margins somewhat raised in the 

 centre, inside white, margin crenulated. 2-p^ . . 2J-. — Chili and 

 Peril. 



V. Crenifera. Sow. Z. P. 1835. — Elliptic, rough, whitish, 

 spotted and variously painted with brown, with short crowded con- 

 centric ridges, decussated by very close set radiating striae : pos- 

 terior cardinal tooth large and elongated. 1J-..1J. — West 

 Columbia. — Variety. Uniform brownish, with some of the striae 

 elevated and riblike. — Peru. 



V. Crassicosta. Quoy. Ast. t. 84. f. 1, 2. Transversely 

 ovate, heart-shaped, rather thick, yellowish grey, with distant thin 

 slightly waved transverse ridges, and equal rounded longitudinal 

 ribs: inside white, with an anterior violet stain ; margin very finely 

 crenated. — New Zealand. 



V. Discors. Sow. Z. P. 1835. Oboval, thickish, with crowded 

 radiating striae, posteriorly decussated by wrinkles ; white, nearly 

 covered with blackish brown, the disposition of the colouring of the 

 two valves different; a rather elevated dorsal line ; inside white, 

 stained with violet on the anterior side, margin crenulated. 14. .l-r%. 



x-v n n 4 ' 510 



— C. 9" S. America. 



V. Fusco-lineata. B?*od. $• Sow. Z. P. 1835. Obovate, 

 whitish, with radiating rib-like striae, which are posteriorly sub- 

 decussated; with waved sub-oblique lines, and sometimes two brown 

 rays ; dorsal edge straightish, anteriorly subangulated ; posterior 

 side short, lunule short ; inside purplish. 1^. .1J.' — C. America. 



V. Leucodon. Sow. Z. P. 1835. Elliptic, thickish, some- 

 what ashy, with concentric smooth reflected rib-like striae, decus- 

 sated by crowded radiating ones ; anterior dorsal area and the lunule 

 brown ; inner margin denticulated, the denticles white, the inter- 

 stices black . 1 -^ . . 1 -?- () . — California . 



