84 



CONCHOLOGY. 



Univalve?. 



Ueteroc.!:. 

 tsu 



xxr. 



It^llD.Ui, 



Ampulla,, 



?atula, 



.'Vperta, 



P/'tiraul.i, 



canaliculated ;■ outer lip smooth; pillar plain, with 

 seven ov eight thread-like striae ; length a quarter of an 

 inch. 



Test. Brit. tab. 29. fig. 5. 



Found by Mr Laskey near Dunbar. 



J). Iieteroclila. Shell glossy, white, veined like ivo- 

 ry in a longitudinal direction, and furnished with eight 

 or nine reversed whorls obtusely pointed ; pillar with 

 one plication ; length a quarter of an inch ; breadth 

 one-third of its length. 



Mem. Wer. Soc. vol. i. tab. 8, fig. 12. 



Found by Mr Laskey near Dunbar. 



We consider the V. bullaoides as scarcely entitled to 

 a place among British shells. 



Genus XXI. Bulla. 



Skrll convoluted; spires usually concealed; month lon- 

 gitudinal, somewhat contracted ; the base entire; pillar 

 smooth ; lip acute. 



A. Dextral. 



1. Lignaria. Shell oval, thin, brittle, yellowish 

 brown, with numerous spiral strise ; mouth extending 

 the whole length of the shell, contracted a little at the 

 upper part ; apex depressed ; pillar visible to the end ; 

 length sometimes nearly two inches. 



Brit. Zool. tab. 70, fig. 83. 



Brit. Shells, tab. 27. 

 Found at Weymouth, Dorset, and in Cornwall and 

 Devonshire; rare. It is common in Scotland, at St 

 Andrew's, in the Frith of Forth, and has likewise been 

 observed in Orkney. 



2. Ampulla. Shell oblong, smooth, glossy, mottled 

 with light chesnut.; no external volution, but the apex 

 is sunk into a considerable cavity • mouth moderately 

 wide ; on the lower end of the pillar lip the shell is 

 thickened, and of an opake white colour; pillar not vi- 



- sible to the end ; length three-eighths of an inch. 

 Test. Brit. tab. 7, fig. 1. 

 Found by Mr Montagu in sand from Falmouth har- 

 bour; but -rare. 



3. Palula. Shell smooth, glossy, white, oblong, the 

 upper end extending beyond the body ; base more ex- 

 tended ; mouth large, terminating in a short canal at 

 each end ; pillar twisted, forming a furrow on its lip ; 

 outer lip plain and very thin ; length one inch ; breadth 

 half an inch. 



Brit. Zool. tab. 70, fig. 85, A. 



Brit. Shells, tab. 14S. 

 Found at Weymouth, according to Mr Pennant and 

 Dr Pulteney. Mr Laskey has likewise found it on 

 Portobello sands, near Edinburgh. 



4. Aperta. Shell sub-orbicular, thin, pellucid, white, 

 without any external convolution or pillar cavity, inner 



ip very small, slightly involuted, visible to the end ;, 

 he mouth occupies nearly the whole of the shell. 

 Length about half an inch. 



Brit. Shells, tab. 120. fig. 1. 

 Test. Brit. vig. 2. fig. 1. 

 First noticed as British by Da Costa. Found in se- 

 veral places on the English shores ; and at Dunbar by 

 Mr Laskey. 



5. Plumula. Shell ovate, oblong, depressed, pellucid; 

 the convolution makes one turn ; it is strongly wrink- 

 led, and possesses two or three ray-like indentations 

 running from the margin towards the apex ; mouth ex- 

 tends the whole length of the shell; length half an 

 ifick 



Test. Brit. tab. 15. fig. %. 

 Found by Mr Montagu at Milton sands, South De- 

 von. 



6. Catena. Shell pellucid,, white, glossy, transversely 

 striated ; apex obtuse without any visible whorl ; mouth 

 very large, occupying almost the whole of the shell ex- 

 cept a small part at the top ; diameter rarely exceeding 

 one-tenth of an inch. 



Test. Brit. tab. 7. fig. 7- 

 Found by Mr Montagu among sand in Bigberry bay 

 Devon ; at Tenby South Wales by Mr Adams, and at 

 Dunbar by Mr Laskey. 



7. Emarginata. Shell pellucid, smooth ; lip subar- 

 cuated. 



Lin. Trans, vol. v tab. 1. fig. 9—11. 

 Found by Mr Adams near Pembroke. 



8. Denlicutaia. Shell white, pellucid, oblong, nearly 

 equal, obtuse, smooth, the mouth at top ending in a 

 very acute tooth. 



Liu. Trans, vol. v. tab. 1. fig. 3, 4, 5. » 



Found near Pembroke by Mr Adams. 



9. HyJatis. Shell oval, sub-pellucid, thin; epider- 

 mis ferruginous ; body tumid, minutely striated trans- 

 versely; no external volution, apex with a cavity; mouth 

 large at the base, contracting a little at the top and ex- 

 tending rather beyond it ; outer lip very thin, pillar lip 

 a little thickened and whitish ; pillar not visible to the 

 end : length one inch. 



Brit. Shells, tab. 88. 

 Not uncommon on the western coast of England ; it 

 has likewise been observed at Dunbar by Mr Laskey. 



10. Akera. Shell thin, elastic, horn-coloured, oval, 

 somewhat wrinkled longitudinally ; apex obtusely cana- 

 liculated ; mouth large at the base, much contracted at 

 the top ; outer lip very thin ; pillar lip a little thicken- 

 ed, white ; inside white ; pillar visible to the end ; 

 length about three quarters of an inch ; breadth nearly 

 half an inch. 



Brit. Shells, tab. 79- B. resiliens. 

 First observed as British by the Rev. Mr Cordiner 

 at Banff; has since been found on several parts of the 

 British coast. 



11. Cylindracea. Shell slender, cylindrical, smooth, 

 glossy, white ; aperture the whole length of the shell, 

 narrow and dilated a little at the base ; apex depressed, 

 with a cavity ; outer lip thin, acute, straight ; inner 

 lip thickened, opake^ white ; pillar a little indented.. 

 Length five-eighths of an inch. 



Test. Brit. tab. 7. fig. 2. 

 Brit. Shells, tab. 120. fig. 2. 2. 

 Not uncommon on the English and Scottish shores. 



12. Umbilicata. Shell oblong, oval, smooth, white; 

 apex rounded with a cavity; mouth narrow, the whole 

 length of the shell, dilating a little at the base ; length 

 one-eighth of an inch ; breadth one half of its length. 



Test. Brit. tab. 7- fig 4 

 Discovered by Mr Montagu amongst sand from Fal- 

 mouth harbour sparingly. 



13. Truncata. Shell subcyhndric, opake, white, the 

 upper part longitudinally striated, the lower plain ; apex 

 truncated with a cavity shewing the involutions ; 

 mouth the whole length of the shell, narrow, dilated a 

 little at the base, and contracted in the middle. Size of 

 the last. 



Test. Brit. tab. 7. fig- 5, 

 Common to the shores of Cornwall and Zetland. 



1 4. Obtusa. Shell moderately strong, sub-cylindric, 

 opake, wrinkled longitudinally ; apex convoluted, ob- 

 tuse j whorls four or five, very little produced ; mouth 



Univalves. 



Cdttns, 



Emargfn?,. 

 ta, 



Den'ticula- 

 ta, 



Hvc?ati«, 



Akera, 



Cylindra- 

 cea, 



Umbilica- 

 tay 



Truncata, 



6btU5a : 





