SAXICAVA. 87 



Oeniis SAXICAVA, Fleurian de Bellevue. (1802.) 



Shell cl<3ngate, irregular, inequipartite, slightly gaping at each 

 end. Hinge generally toothless or witli only a rudimentary tooth 

 in each valve ; beaks small ; ligament external, long, strong ; pallial 

 sinus narrow and deep. 



Saxicava rugosa. 



Shell multiform, generally oblong, rounded before and truncate behind, with a 

 prominent ridge from the beaks to the lower posterior angle ; surface rough. 



MijtiJm rugosus, Penn. Br. Zool. iv. 110, pi. 63 fig. 72. — Montagu, Test. Brit. 42. pi. 1. 



fig. 1. — DoNOv. Br. Shells, iv. 141, fig. 141 ; Linn. Trans;, viii. 105; Dorset Catal. 



39, pi. 13, fig. 5. — TuRT. Conch. Diet. 113. — Dillw. Recent Shells, i. 304. — 



Wood, Ind. Test. pi. 12, fig. 9. 

 Saxicaca riiqoxa. Lam. An. sans" Vert. 2(1 ed. vi. 152; Spec, of Shells, Engl, ed. 50. — 



TuRT. Dyth. Brit. 20, pi. 2, fig. 10. — Browx, III. Conch. Gr. Brit. 103, pi. 47, 



figs. 14, 16. — Crouch, Introd Conch, pi. 5, fig. 3. — Sowerby, Gen. (Saxicava) 



fij:s. 2, 3, 4. — Reeve, Conch. Icon. i. pi. 50, figs. 2, 3, 4. — Woodward, Man. of 



Moll. 320, pi. 22, fig. 13. — Hani.ey, Recent Shells, Suppl. 50. — Forbes and Hanl. 



Hist. Brit. Moll. i. 146, pi. 6, figs. 7, 8, pi. F, fig. 6 (animal). —Chenu, Man. de 



Conch, ii. 25^ fig. 1 11. — Adams, Gen. 349, pi. 94, figs. 1, 1 a, 1 6 (animal). — Stimp- 



SON, Mar. Inv. Gr. Manan, 22 ; Shells of New England, 25. 

 Ulntella riir/osn, Flem. Br. Anini. 461 ; Brit. Mar. Conch. 58. 

 Mi/fi/u'i /)Iioladis, MuLLER, Zoo). Dan. pi. 87, fi^s. 1, 2, 3. 

 Saxicava pholadis. Lam. An. sans Vert. 2d ed. vi. 152. — Turt. Dyth. Brit. 21, pi. 2, 



fig. 11. — Hanl. Recent Shells, .50. — Guerin, Mag. de Zool. 1841, pi. 40. 

 Saxicnve ride'e, Chenu, Trait. Elem. 58, figs. 197, 198 

 Bjssowija pholadis, Bowditch, Bivalves, fig. 43. — De Blainv. Man. 572, pi. 80, figs. 



5, 5 a. 

 Mi/(i hyssi/era, O. Fabr. Fauna Gnenl. 408. 

 Saxicava distortti, Say, Journ. Ac. Nat. Sc. ii. 318 (1822). — Gould, Inv. Mass. 1st ed. 



62. — De Kay, Nat. Hist. New York, 227, pi. 33, figs. 309 «, 309 6. 



Animal with the mantle lobes united in front ; siphons large, 

 vmited nearly to their ends, which are fringed, the anal opening 

 furnished with a transparent tubular valve ; o])eiiing for the foot 

 small ; foot finger-like, with a byssal groove ; gills narrow, unequal, 

 prolonged into the siphon. 



Shell ol)long-oval, coarse, white, very irregular in shaj^e ; inequi- 

 valve, the right valve projecting over the left except at the sliorter 

 end ; inequilateral, the anterior side rounded and generally of about 

 one half the length of the other side, but the beaks are sometimes 

 nearly terminal ; the posterior end is most frequently truncated, 

 but at other times rounded ; gaping ; beaks rather prominent, from 



