CONCH OLOGY. 



91 



Camaria, 



Bivalve?. Jng a little to one side ; hinge furnished with two teeth 



s — ~Y~~*' in" the one valve, and one in the other ; by the side of 



the teeth in each valve a deep groove, into which the 



connecting cartilage is fixed ; diameter three quarters 



of an inch. 



Test. Brit. tab. 2, fig. 4. 

 Found on various parts of the English coast. 

 Boiundata 16. Rotundata. Shell thin, sub-pellucid, orbicular, 

 white, rather convex, wrought with fine concentric 

 striae ; beak nearly central, small, turned to one side ; 

 teeth two in each valve, one of which is bifid, the other 

 a little diverging; inside smooth, glossy; diameter about 

 an inch. 



Test. Brit. tab. 2. fig. 3. 

 Found on the shores of Dorset, Devon, and Corn- 

 wall. 

 Flcxuosa, 17. Flexuosa. Shell thin, pellucid, fragile, convex, 



sub-orbicular ; from behind the beak to the lower angle 

 of the margin, a sulcus runs parallel with the cartilage 

 slope, and forms a flexure at the edge ; beak nearly cen- 

 tral, much produced, turning to one side ; hinge with an 

 obsolete tooth ; diameter about three-eighths of an inch, 

 Brit. Shells, tab. 42. fig. 2. Venus sinuosa. 

 Found in Cornwall and Devon by Mr Montagu ; and 

 at Portobello sands by Mr Laskey. 



18. Carnaria. Shell sub-orbicular, flattish, with one 

 side rather longer than the other ; striated in three di- 

 rections ; beak small, nearly central, and turning a lit- 

 tle to one side ; hinge in one valve furnished with two 

 small teeth, one of which is bifid, in the other with 

 one tooth ; lateral teeth laminated, remote ; length 

 three quarters of an inch ; breadth seven eighths. 

 Brit. Shells, tab. 47. 

 First noticed by Da Costa, from Yoi-kshire, Devon- 

 shire, and Cornwall. Dr Pulteney found it sparing- 

 ly at Poole and Weymouth. 

 Maculata, 19. Macidata. Shell sub-ovate, strong, striated lon- 

 gitudinally and transversely ; irregularly spotted. 

 Lin. Trans, vol. iii. p. 252. 

 Found at Tenbigh by Mr Adams. 

 Polygona, 20. Polygona. Shell sub-ovate, sub-orbicular, wrought 

 with fine concentric striae which are crossed with very 

 fine lines ; beak small, the shorter end is a little trun- 

 cated and angulated ; the larger end is rounded ; inside 

 smooth, margin uneven ; teeth, in one valve, two large 

 and distant, in the other, one, very large, triangular, 

 bifid tooth, with an approximate small one. 

 Test. Brit. tab. 28, fig. 4. 

 Dredged up by Mr Laskey off Cramond Island, in the 

 Frith of Forth. 

 Laslceyi, 21. Laskeyi. Shell ovate, oblong, smooth; beak 



scarcely central, obtuse ; one of the sides rounded, the 

 other obtuse ; inside white round the margin, and 

 smooth ; in one valve there are two approximate sub- 

 bifid teeth, and the margin channeled from the teeth 

 almost to the end of the longest side, and on the other 

 side of the teeth the margin is replicated ; the other 

 valve has only a single tooth; length half an inch; 

 breadth three quarters. 



Test. Brit. tab. 28, fig. 3. 

 Found by Mr Laskey in Aberlady bay and Mussel- 

 burgh sands, in the Frith of Forth. 



Genus XXX. Pandora. 



XXX. Shell regular, inequivalved and inequilateral, tuilh two 



Pandora, oblong, unequal, and diverging hinge-teeth in the supe- 

 rior valve, and two oblong corresponding pits in the other 

 valve ; the cartilage interior ; two muscular impressions. 



Obs. This genus was formed by Lamarck, for the Bivalves 



purpose of separating the Linnaean Tel/ina in&quivahis "*" ""Y"^"^ 

 from a family of shells with which it is very remotely 

 connected. 



1. Inmquivalvis. Shell oblong, sub-pellucid, white ; Inxquival. 

 left valve nearly flat, the other convex, sub-arcuated vii « 

 along the cartilage slope, and extending into a consi- 

 derable obtuse beak at that end ; the other end round ; 

 in the flat valve two diverging teeth, the anterior one 

 small ; from the beak to the longest side, a longitudi- 

 nal depression ; length half an inch ; breadth one inch. 

 Brit. Shells; tab. 41, fig. 1, Tellina inceqidvalvis. 



First described as British by Mr Donovan. Accord- 

 ing to Dr Maton and Mr Rackett, small ones are found 

 on the Kentish coast. 



Genus XXXI. Corbula. 



Shell transverse, inequilateral, inequivalved, ivilh pro- XXXI. 

 miucnt incurved bealcs ; hinge with a single conical re- Corbula. 

 curved tooth in each value ; ligament internal; two late- 

 ral impressions. 



1. Inmquivalvis. Shell subtriangular, strong ; under I"*<jui- 

 valve deep, and larger than the upper valve ; beak pro- valvl3 * 

 minent, standing high above the hinge ; outside cover- 

 ed with a brown epidermis ; inside smooth, the mar- 

 gin appearing as if ground to an edge ;" length three- 

 eighths of an inch. 



Test. Brit. tab. 26. fig. 7- Mtja inaquivalvis. 



This shell we have ventured to remove from the Mya>, 

 and to place in the genus Corhda of Lamarck, with the 

 characters of which it seems most exactly to correspond. 

 It is a very common shell on the English and Scottish 

 shores. 



Genus XXXII. Cardium. 



Shell cquivalved, convex, longitudinally ribbed, with a XXXIL 

 toothed margin ; hinge with two teeth near the beak, and ^*hd"Jm» 

 a larger remote lateral one on each side, locking into the 

 opposite valve. 



1. Edule. Shell with about twenty-six antiquated Edule, 

 ribs, of a yellowish-white colour ; the anterior end a 

 little elongated, and generally of a darker colour ; great- 

 est diameter about an inch and three quarters. 



Brit. Zool. tab. 50, ^ig. 41. 



Brit. Shells, tab. 124. 

 This is the common cockle, and is found in great 

 plenty on the British shores, in the sandy bays and in- 

 lets. 



2. Aculealum. Shell convex, posterior side rounded, Aculeatunv, 

 the other nearly straight, and more elongated at the 



front marginal angle ; ribs about twenty-one, with a 

 depressed line down the middle ; the round end beset 

 with large compressed tubercles, the other part to- 

 wards the margin with spines ; length about four 

 inches. 



Brit. Shells, tab. 6. 

 Common in various parts of the English and Scot- 

 tish shores. The young of this species have been long 

 known as Cardium ciliare. They are destitute of spines. 



3. Echinatum. Shell very convex, having alxmt Echinatum, 

 eighteen ribs furnished with numerous close set con- 

 vex spines ; diameter about two inches and a half. 



Brit. Shells, tab. 107, fig. 1. 

 Common on our shores. 



4. Lavigatum. Shell sub-oval, striated longitudinal- Lasv 'ga- 

 ly, with a few concentric wrinkles ; anterior side a lit- tum ' 



