45 

 BULL.EA. 



GENERIC CHA RACTER: The shell thin, partially rolled 

 and spiral on one side; without columella or spire; aper- 

 ture large, dilated at the upper part. 



B. APERTA. Bulla A. Turt. Lin. Mont. Test. Brit., 

 vol. 1, p. 208, pi. vignette, 2 part, fig. 1. Flem. Brit. 

 An., p. 294. Rare. I have met with a specimen much 

 resembling Montagu's account of this shell, but differing 

 sufficiently to require mention; chiefly at the junction of 

 the pillar with the expansion, where the whorl is twisted, 

 and tapers up to join the wing. Length six twentieths of 

 an inch, a little more than four twentieths of an inch 

 wide; white, and slightly transparent. 



BULLA. 



GENERIC CHARACTER: The shell oval, globular, 

 convolute; no columella, or projecting spire, or only 

 slightly elevated ; aperture the length of the shell, outer 

 margin sharp. 

 Bulla differs from Bnllsea, hy the shell being completely 



convolute, always visible external!}', which the latter is not; 



and only partially covered by the hinder part of the animal. 



* B. LIGNARIA. Turt. Lin. Pen. Brit. Zo., vol. 4, 

 pi. 70, fig. 83. Borlase's Nat. Hist, Corn., pi. 28, fig. 14. 

 Mont. Test. Brit., vol. 1, p. 235. Flem. Brit. An., 

 p. 292. Not uncommon, chiefly in trawls. 



B. AMPULLA. Mont. Test. Brit., vol. 1, p. 206, pi. 7, 

 fig. 1. Flem. Brit. An., p. 292. Montagu found two 

 or three of what he believed to be this species, in sand 

 from Falmouth harbour. 



B. UMBILICATA. Mont. Test. Brit., vol. 1, p. 222, 

 pi. 7, fig. 4. Flem. Brit. An., p. 293. Found by Montagu 

 sparingly, amongst sand from Falmouth harbour. 



• B. CYLINDRACEA. Pen. Brit. Zo., vol. 4, pi. 70, fig. 85. 



Mont Test. Brit., vol. 1, p. 221, pi. 7, fig, 2. Flem. Brit., 

 An., p. 293. Found by Montagu at Falmouth, and I have 

 obtained it from the byssus of a Pinna. 



B. TRUNCATA, Turt. Lin. Mont. Test. Brit., vol. 1, 

 p. 223, pi. 7, fig, 5. Flem. Brit. An., p. 293. Found by 

 Montagu, not uncommon in sand at Falmouth. 



B. PATULA, Pen. Brit. Zo., vol. 4, pi. 70, fig. 85. A. Mont, 

 lest. Brit., vol. 1, p. 207. I have obtained it from the 

 depth of 40 fathoms, on a branch of Gorgonia Verrucosa. 



CO LI MACE A 



The shell spiral, with no other projecting part on the outer 

 surface, than the lines of growth; the right margin of the 

 aperture olten recurved, or reflected outwards. 



