COXCHOLOGY. 



379 



nicemt arietina, pi. is, f. 30. Adherent, inequivalve ; 

 bt-aks very large, conical, divergent, irregularly spiral ; greater 

 vulve with a large thick tooth. 



SECTION II. LAMBLLIPIDES. 



FAMILY I. NAYADES. 



Inhabit fresh water. 



Iridina exotica, pi. 18, f. 31. Equivalve, inequilateral, 

 transverse ; beaks email, nearly straight ; hinge elongated ; 

 tuberculous ; ligament exterior aud marginal. 



Anadonla cygnea, pi. is, f. 32. Inequilateral, equivalve, 

 transverse ; hinge linear ; no teeth. 



Hyria corrugata,.p], 18, f. 33. Equivalve, trigonal, auricu- 

 lated ; two spreading teeth, pusterior one divided into diver- 

 gent portiors. anterior one strong, lamellar. 



Vnio irroiatia, pi. 18, f. 34. Equivalve, transverse; two 

 teeth in each vulve, one short, divided ; the other elongated, 

 com pressed. 



FAMILY II. TRIGONACEA. 



Cn.italia ambigua, pi. is, f. 35. Equivalve, inequilateral, 

 beaks posteriorly recurved : two lamellar teeth ; posterior re- 

 mote, shortened ; the other anterior, elongated, lateral. 



Trigonia tcabra, pL 18, f. 36. Equivalve, inequilateral, tri- 

 gonal, or orbicular : primary teeth oblong, divergent, and 

 Battened on the sides ; two in the right valve aud a groove on 

 one side ; ligament exterior, marginal. 



FAMILY III. ARCACEA. 



ffucula tenuit, pi. 18, f. 3T. Equivalve, inequilateral, tri- 

 gonal. or oblong; hinge with numerous teeth ; a central ob- 

 lique hollow ; beaks bent backwards ; ligament marginal. 



Pectunculus pilosiu, pi. 18, f. 38. Orbicular, equivalve, sub. 

 equilateral ; teeth numerous, oblique ; ligament external. 



Area tortuota, pi. 18, f. 30. Transverse, subequi valve, ine- 

 quilateral ; teeth numerous, parallel ; ligament external, 



Cucullcea auriculifera, pi. is, f. 40. Inequilateral, equivalve, 

 gibbous ; teeth numerous, small, parallel ; ligament external. 

 FAMILY IV. CARDIACEA. 



Isocardia Moltkiana, pi. 18, f. 41. Equivalve, ventricose, 

 heart-shaped ; beaks much apart, divergent, spirally twisted ; 

 primary teeth :, flattened ; lateral tooth placed under the liga- 

 ment, which is exterior- 



Hiatella arctica, pi. 19, f. 42. Equivalve, inequilateral 

 transverse; upper margin gaping ; teeth two, small audiiidis. 

 tinct, fitting into cavities in the opposite valve. 



Cypricardia corattiophaga, pi. is, f. 43. Equivalve, inequila- 

 teral, obliquely elongated ; 3 primary teeth ; a lateral tooth 

 under the beaks. 



Cardita ciasiicotta, pi. 19, f. 44. Equivalve, inequilateral; 

 2 unequal teeth ; one short and straight, the other oblique. 



Cardium elongatum, pL 18, 45. Equivalve, subcordiform ; 

 beaks produced ; internal margins oentated ; 4 teeth in each 

 valve, two primary ones, approximate and oblique, lateral 

 ones distant. 



FAMILY V. CONCHACEA. 



Venericardia imbricata, pi. 18, f. 46. Equivalve, equilateral ; 

 suborbicular ; generally longitudinally ribbed; 2 oblique pri- 

 mary teeth. 



"Orti/gta sulcata, pi- 18, f. 47. Equivalve, transverse ; three 

 teeth in each valve, two approximate ; ligament subexternal. 



Venut verrucosa, pi. 18, i. 48. Equivalve, inequilateral ; 3 

 primary teeth in each valve ; lateral ones divergent ; ligament 

 external. 



Cytherea erycina, pi. 18, f. 49. Equivalve, inequilateral ; 

 generally suborbicular ; 4 primary teeth in the right valve, 3 

 of which are divergent ; other valve with three diverging pri- 

 mary teeth. 



*Exoleta lineta, pi. 18, f. 50. Equivalve, orbicular, inequi- 

 lateral ; beaks much turned to one side ; three primary teeth, 

 two contiguous, one divergent ; cartilage subinternal. 



Cypnna Islandica, pi. 18, f. 51. Equivalve, inequilateral ; 

 obliquely curdiform ; beaks oblique ; three primary teeth, un- 

 equal, approximate at their base, divergent above ; a remote 

 lateral tooth. 



Laeea rubra, pi. 18, f. 52. Equivalve, inequilateral ; umbo 

 prominent ; hinge with two nearly obsolete primary teeth ; 

 lateral distinct teeth. 



Galathea radiata, pi. is, f. 53. Equivalve, subtrigonal ; two 

 primary furrowed teeth in the right valve, three in the left ; 

 lateral teeth remote, ligament external. 

 on 



teeth contiguous to the 

 primaries ; ligament external. 



Cyclai cornea, pL is, f. 55. Equivalve, oval, gibbous, 

 transverse ; primary teeth, two in each valve, extremely small, 

 one divergent ; lateral tooth elongated, lamelliform ; ligament 

 external. 



*Pitidium ob'iqua, pL 18, f. 56. Equivalve, transverse ; right 

 valve with one, and the left valve with two small primary 

 teeth ; behind and before two thin lamellar teeth, clcU in the 

 right valve. 



SECTION III. TENUIPBDES. 



FAMILY I. NYMPHACEA. 



Crassina sulcata, pL 18, f. 57. Kquivalve, suborbicular, 

 transverse ; right valve with two strong teeth ; left valvti two 

 unequal ones ; ligament external. 



Capsa Braziliensii, pi. 18, f. 58. Eqnivalve, transverse ; 

 right valve two teeth, a bifid tooth in the leit; ligaineut ex- 

 ternal, 



Cyrena futcata, pL 18, f. 54. Trigonal, ventricose, thick ; 

 three teetfi in each valve ; two lateral te 



Donor denticulata, pi. 18, f. 59. Equivalve, transverse, in- 

 equilateral; one or two primary teeth in each valve, anil one 

 or two lateral ones ; ligament exterior, short. 



Lucina camaria, pL is, f. 60. Inequilateral, snborbicnlar : 

 two primary divergent teeth, one of them bind ; two lateral 

 teeth ; ligament external. 



*Mysia rotundata, pi. 18, f. 61. Suborbicular, inequilateral 

 hinge with two primary teeth, united at their base and diver- 

 gent ; behind these an oblique descending cavity ; ligament ex- 

 ternal. 



Corbis lamellosa, pL 18, f. 62. Equivalve, transverse ; beak? 

 bent inwards ; two primary teeth and two lateral ones ; mus- 

 cular impression simple. 



*Arcopagiacrassa, pi. 18, f. 63. Equivalve, transverse; 

 valves subdepressed, two primary teeth in each, the larger 

 ones cleft ; left valve with two lateral teeth, fitting into clefts 

 in the opposite valve ; muscular impressions very large. 



Tellinidei roseui, pL is, f. 64. Inequilateral, transverse ; 

 depressed ; two teeth in each valve divergent ; two nearly ob- 

 solete teeth in one valve. 



Tellina punicea, pi. 18, f. 65. Orbicular or transverse ; usu- 

 ally depressed ; anterior side angular ; margin flexuoiis ; one 

 or two primary teeth in the same valve ; two lateral teeth. 



Psammot&a variegata, pi. 18, f. 66. Transverse, ovate-ob- 

 long ; gaping slightly at the sides ; one primary tooth in each 

 valve, or in one only ; ligament external. 



Psammobia vtspertina, pL is, f. 67. Transverse, elliptical, 

 depressed ; gaping slightly on each side ; two teeth in the left, 

 and one in the right valve ; ligament external. 



Sanguinolaria Occident, pL IS, f. 68. Transverse ovate ; up- 

 per margin produced ; 2 approximate teeth in each valve. 

 FAMILY II. LITHOPHAGI. 



Venerupis irut, pi. is, f. 69. Transverse inequilateral ; pos- 

 terior side short ; anterior gaping slightly ; two teeth in the 

 right and three in the left valve ; sometimes three in each ; liga- 

 ment external. 



Petricola Pholadiformis, pi. 18, f. 70. Inequilateral, subtri- 

 gonal, transverse ; posterior side rounded ; anterior side atten- 

 uated ; gaping slightly ; two teeth in cuch valve ; sometime* 

 but in one. 



Saxicava Proecisa, p). 18, f. 71. Transverse, inequilateral; 

 gaping anteriorly ; teeth nearly imperceptible ; ligament ex- 

 ternal. 



FAMILY III. COBBULACEA. 



Pandora rostrala, pi. 18, f. 72. Inequivalve, inequilateral, 

 transverse ; upper value depressed, under one convex ; two 

 primary teeth in the upper valve, fitting into two grooves in the 

 under one; ligament internal. 



Corbuta rulcata, pi. 18, f. 73. Inequivalve, inequilateral ; on* 

 primary ascending tootli in each valve, with a hollow pit at its 

 side ; no lateral teeth ; ligament internal. 



FAMILY IV. MACTRAC^A. 



Amphidesma Litcinalu, pi. IS, f.74. Inequilateral, transverse ; 

 eubovate; sometimes gaping at the sides ; one or two teeth ; 

 ligament double. 



Svlemya Mediterranea, pi. IS, f. 75. Inequilateral, transverse, 

 ends obtuse ; one compressed primary oblique tooth in each 

 valve ; ligament subexternal. 



*Telltmya suborbiculnrii, pL 18, f. 76. Inequilateral, suborbi- 

 cular, or transverse ; right valve with two recurved primary 

 teeth ; left none. 



Vngulina tratistersa, pi. 18, f. 77. Nearly equilateral, longi- 

 tudinal or transverse ; in each valve a short, slightly cleft, pri- 

 mary tooth, and a divided groove; ligament internal. 



Erycina striata, pi. 18, f. 78. Subinequilateral, transverse, 

 sometimes gaping ; two diverging primary teeth, with an in- 

 terposed hollow; two oblong lateral teeth ; ligament internal. 



Crassatella Kingicola, pi. 18, f. 79. Inequilateral ; roundish, 

 sometimes transverse ; two primary teeth, sub-divergent, a 

 hollow pit on their side ; no lateral teeth ; ligament internal. 



*Ligula tennis, pi. 18, f. SO. Subequilateral ; one broad trails- 

 verse tooth, with a central cavity for the reception of the liga- 

 ment. 



*Mactrina triangularit, pi. 18, f.81. Subtriangular, inequi- 

 lateral, left valve with a strong triangular slightly bifid tooth ; 

 aud on each side are pits for the reception of two depressed 

 lateral teeth in the opposite valve, which have a pit interven- 

 ing ; ligament external. 



Matra Stultorum, pi. 19, fig. 1. Subinequilateral, subtrans- 

 verse, subtrigoual ; sides slightly gaping ; each valve with OHH 

 primary compressed tooth, and two lateral leetl , a heart. 

 shaped cavity contiguous to the umbo ; ligament internal. 



l.utrnria compresta, pi. 19, f. '2. Inequilateral, transverse- 

 oblong, extremities gaping; a triangular tooth, aud an oblique 

 deltoid transverse hollow ; ligament internal. 



SECTION IV. CRASSIPEDES. 



Posterior margin gaping. 



FAMILY I. MYARIA. 



Anatina convexa, pi. 19, f. 3. Subeqnivalve, transverse, gap- 

 ing ;.t one or both sides ; one horizontal spoon- shaped project- 

 ing tooth in both valves, a lateral plate beneath ; ligament in- 

 ternal. 



Mi/ii arenaria, pi. 19, f. 4. Inequivalve, transverse, gaping 

 at both ends ; left valve with a vertical, projecting thick tooth ; 

 none in the other ; ligament internal. 



*Galeomma Turtont, pi. 19, f. 5. Equivalve, inequilateral 

 transverse, front margin with a gape ; no teeth ; ligament in 

 ternal. 



*Magdala itriuta, pi. 19, f. 6. Inequivalve, transversely 

 ovate; gaping at one end ; no teeth; hinge provided wit> 



