144 



CONCHIFERA. 



Anomia. 



front, but entirely confluent behind ; hinge destitute of a liga- 

 ment or teeth. 



1. HippoNYX coRNUCOPLE. — The Horn of Plenty Hip- 

 ponyx, pi. LVI.» fig. 41, 42, 43, 44, 45. 



Piliopsis cortnimpcF. Lamarck, An. San. Vert. VI. pt. 2, 

 p. 19. Desheyes, 609 ; Foss. pi. 2, fig. 13, 14, 15, 16. 



Lower Talve a depressed cone, with the vertex nearly cen- 

 tral, and slightly inclining, crossed by rugose Hues of growth ; 

 upper valve very conical, with its apex inclining considerably ; 

 surface girdled by many irregular rugose lines of growth, 

 with numerous slightly undulating divergent longitudinal stria-. 



The London Clay, Braeklesham, and Grignon, France. 



2. HippoNYx L^Evis. — The Smooth Hipponyx, pi. LVL* 

 fig. 46, 47, 48, 49, 50, 51. H.laivis. Sowerby, Gen. Rec. 

 and Foss. Shells, No. I. 



Lower valve nearly flat ; upper valve oblique, extremely 

 conical, and the whole surface smooth, with a few regular 

 Hues of growth. 



Loudon Clay, Barton, Hampshire. 



Genus XV. CALCEOIjA.— Lamarck. 



Generic Character. — Shell equilateral, inequivalve, trian- 

 gular ; umbones separated by a large, depressed, irregularly 

 and transversely striated, trigonal area in the lower valve, 

 which is the larger of the two, and very deep, funnel-shaped, 

 and obliquely truncated at its upper side ; hinge margin trans- 

 versely straight, linear, notched, and slightly toothed in the 

 centre ; the upjjer edge arcuated ; upper or smaller valve semi- 

 orbicular, semioircularly striated, and serving as a lid to the 

 lower valve ; internal cardinal edge furnished with two lateral 

 tubercles, a central pit and smaller plate. 



1. Calceola sandalina. — The Sandal-shaped Calceola, 

 pi. LVL* fig. 52, 53. 



C. calceola. Phillips, Pal. Foss. p. 137, pi. 60, fig. 102.' 



Devonian Shales, Chircombe Bridge, near Newton, South 

 Devon. 



Sdb-Division II. 



Ligament not marginal, but placed in a short hollow under 

 the beak, always perceptible, and not forming a tendinous 

 cord beneath. 



Family I. OSTRACEA. 



Ligament placed either interiorly or nearly so ; shell irre- 

 gular in form, foliaceous and sometimes papyraceous. 



Sub-Division I. 

 Ligament placed interiorly ; shell thin, papyraceous. 



Genus XVI. ANOMIA.— Ziwwaws. 



Generic Character. — Shell inequivalve, irregular, opercu- 

 lated ; under valve flattened, with a large circular or ovate 

 perforation near the hinge, and its edges turned back, through 

 which protrudes a testaceous or bony, straight, elliptical oper- 

 culum or plug, with a dilated base, by which the shell adheres 

 to extraneous bodies ; upper valve the larger, concave and 

 entire ; ligament large, transverse, internal, placed within the 



upper valve, at the umbo, and attached to a prominent, ex- 

 panding appendage in the depressed valve ; lower valve with 

 a single, orbicular, nearly central muscular impression ; upper 

 valve with three impressions, situated contiguous to each other, 

 the largest is next the base of the shell, which is connected, by 

 means of its muscle, with the plug, and the other two are also 

 connected, by the medium of their muscle, with the single im- 

 pression in the lower or flattened valve. 



1. Anomia lineata. — The Lineated Anomia, pi. LVII. 

 fig. 5, 6, J, 8. 



A. striata. Sowerby, V. p. 32, pi. 425. 

 Suborbicular, convex ; surface with fine numerous distinct 

 radiating strife. 



In the adult condition it is contracted towards the beak. 



Loudon Clay, Barton and Bagnor. 



2. Anomia semistriata. — The Semistriated Anomia, pi. 

 LVL fig. 23. 



A. semistriata. Bean, Mag. Nat. Hist. New Series, III. 

 p. 61, fig. 21. 



Elliptical, a little convex, and thick, with concentric lines of 

 growth, and numerous longitudinal undulating striw, which 

 are only visible from about the centre of the valve to the 

 margin ; umbo small and acute, situate nearly central. Length 

 one inch, breadth three quarters, 



Combrash, Scarborough. 



3. Anomia aculiata. — The Spined Anomia, pi. LVII. 

 fig. 17. 



A. aculiata. Brown, Illust. Rec. Conch. Brit. p. 70, pi. 

 22, fig. 6. 



Orbicular, compressed, with numerous raised divergent strise, 

 surmounted by concave obtuse murications, or spines ; um- 

 bones small, inclined ; under valve flat and smooth. Diameter 

 three-eights of an inch. 



Pleistocine Marine Formation, Ayrshire, and Ireland. 



4. Anomia ephippium. — The Saddle-shaped Anomia, pi. 

 LIX. fig. 13. 



A . ephij/pium. Brown, Illust. Rec. Conch., Brit. p. 69, pi. 

 22, fig. 1 and 4. 



Suborbicular, irregularly waved and wrinkled ; one valve 

 convex, the other flat ; perforation rather large. 



Pleistocine Marine Formation, England and Sufi'olk Crag. 



5. Anomia convexa. — The Convex Anomia, pi. LVII. 

 fig. 18, 19. 



A. conrexa. Sowerby, Geo. Trans. 2d Ser. IV. p. 338, 

 pi. 14, fig. 7. 



Remarakably convex ; beak large and prominent ; surface 

 smooth. 



Lower Greensand, Shanklin, Isle of Wight. 



6. Anomia l.«vigata. — The Smooth Anomia, pi. LVII.* 

 fig. 20, 21. 



A. Icerigata. Sowerby, Geo. Trans. 2d Ser. IV. p. 338, 

 pi. 14, fig. 7. 



Nearly circular, very thin and flat ; surface smooth ; umbo 

 hardly elevated. 



Lower Greensand, Sandgate. 



7. Anomia undulata. — The Waved Anomia, pi. LIX. 

 fig. 14. 



A.tmdulata. Brown, Illust. Rec. Conch. Brit. p. 69. pi. 

 22, fig. 2, 3. 



Strong, flat, and suborbicular, with numerous strong, elevat- 



