Bulla. MOLLUSCA. BRANCHIFERA. 293 



Length -^ths, breadth T 4 5 ths of an inch ; translucent, horn-coloured ; striae 

 In bands, slightly waved by indistinct lines of growth ; the pillar-lip is a little 

 reflected, forming a pillar cavity, and is slightly waved where it joins the 

 outer lip ; the latter projects very little ; the apex is concave, without visi- 

 ble whorls. The specimen from which the preceding description was taken 

 was sent me, under the above title, several years ago, by my friend Dr Leach. 

 The detailed description of its characters may be expected in his long wished- 

 for work on the British Molluscous Animals. 



174. B. ampulla. — Shell oblong, ovate, smooth, mottled with 

 brown. 



Mont. Test. Brit. ccvi. t. vii. f. 1, — In Falmouth Harbour, Montagu; Dun- 

 bar, Laskey. 

 Length |ths of an inch ; opake ; aperture moderately wide ; on the lower 

 end of the pillar-Up the shell is thickened, of an opake colour, but the dupli- 

 cature does not spread up the body of the shell. Montagu was probably mis- 

 taken in referring his species to the Ampulla of Linnaeus, with which it does 

 not agree in shape or form of the aperture. 



175. B. umbilicata. — Shell oblong-oval, smooth ; aperture 



narrow, a little dilated anteally. 



Mont. Test. Brit, ccxxii. t. vii. f. 4. Turton, Conch. Diet. 22. — Coast of 

 England and Ireland. 



Length ith of an inch ; breadth T ' g th ; of a while colour ; apex rounded in- 

 to a cavity. 



176. B. cylindracea. — Shell lengthened cylindrical ; aperture 

 narrow ; pillar-lip with an indistinct fold. 



C. V. exigua alba vere cylindracea, List. Conch, t. Dccxiv. f. 70. — B. cyl. 

 Perm. Brit. Zool. iv. 117- t. lix. f. 85. Don. Br. Sh. t. 120. Mont. 

 Test. Brit. xxi. t. vii. f. 2 — In sandy bays, common. 



Length |ths of an inch ; smooth, glossy white ; outer lip thin, straight ; 

 pillar-lip thickened with an oblique fold ; apex truncated, depressed Per- 

 haps this species should be transferred to the genus Volvaria of Lamarck, as 

 he has hinted. 



177. B. truncata. — Shell subcylindrical, truncated, and deep- 

 ly marked with the lines of growth retrally, rounded and smooth 

 anteally. 



B. crassa, Walk. Test. Min. xvii. t. iii. f. 62 B. tr. Adams, Linn. Trans. 



vol. v. 1. t, i. f. 12. Mont. Test. Brit. 223. t. vii. f. 5 Not uncommon- 



Length about the eighth of an inch, white, closely pellucid ; aperture nar- 

 row, opposite the body, suddenly widening at the pillar, exhibiting the in- 

 ternal volutions ; apex with a cavity. 



— 178. B. obtusa. — Shell subcylindrical ; apex exhibiting a pro- 

 jecting obtuse spire of three or four wliorls. 



Voluta alba opaca longitudinaliter striata, Walk. Test. Min. 17. t. iii. f. 

 61 — B. ob. Mont. Test. Brit. 223. t. vii. f. 3, common. 



Length |ths, breadth ith of an inch, with a brownish epidermis ; lines of 

 growth distinct; aperture narrow retrally, widening at the pillar; outer lip 

 slightly incurved in the middle. 



