\VORMS. TESTACEA. 52. Bulla. 169 



slightly wrinkled longitudinally, umbilicate at top 

 without volution. 



MentagueFign. i.f. 1-5. Da Costa t. i.f. 10. Donovan t. 88. 



She U an inch long, 3 quarters broad, very open but contracted at 

 the upper end, greenish or yellowish-horn-colour, fometimes 

 finely striate tranfverfely : pillar not visible to the end. 



g5j. B. Akera. Oval, membranaceous, horn-colour, 

 with a convolute truncate channelled crown. 



Donovan t. 79. B. resiliens. 



Shell about 3 quarters of an inch long, nearly half broad, pellucid 

 elastic, slightly wrinkled tranfveri'ely, white within: aperture 

 much contracted at top : pillar visible to the end. 



g54. B. cylindracea. Cylindrical, slender, smooth, white, 

 deeply umbilicate; aperture very narrow, a little 

 dilated at the base. 



Br. Zool. t.jo.f. 85. Donovant. 12O./. 2. Mont, t. j.f. 2. 



Shell about 6 lines long, 2 broad : pillar a little indented, without 

 volutions, but only deeply umbilicate : aperture linear, a little 

 wider at the baCe. 



355. B^ umbilcata. Oblong-oval, smooth, white, rounded 

 and umbilicate at the top; aperture very narrow, a 

 little dilated at, the base. 



Montague Brit. Shells p. 222. tab. 7*f. 4. Minute. 



Shell refembling the last but is not fo cylindrical, and its breadth 

 is about one half its length. 



356. B. retusa. Subcylindrical, opake, white, longitudi- 

 nally striate on the upper-part, truncate and umbili- 

 cate at top; aperture very narrow, a little dilated 

 at the base. 



Mantague t. -j.f. 5. Linn. Trans, v. tab. i.f. i. 2. 

 5 hell minute, with confpicuous involutions. 



fcoT. B. obtusa. Subcylindrical, opake, white, longitu- 

 dinally wrinkled, convolute and obtuse at top ; aper- 

 ture narrow, dilated at the base. 



Montague tab. j.f. 3. Walker min. Shells J. 62. 



,Sfe// ; about 3 lines long, half as much broad, often covered with 

 a chefnut skin, with 4 or 5 slightly produced whorls ; aperture a 

 little compressed in the middle, not reaching quite to the top. 



j58. B. diaphana. Suboval, smooth, pellucid, white, ven- 

 tricose, with 3 or 4 somewhat pointed whorls at top; 

 aperture closed at top, very open below. 



Montague. t. j.f. 8. Br. Zool. t. 7 i.f. 87 ? 



ShfU about 4 lines long, 3 broad, slightly .produced to a point at 

 top : pillar plain, not visible to the end. 



359. R. fontinalis. Oval, pellucid, light ^horn-colour, 

 ventricose, with 4 or 5 reversed, hardly produced 

 obtuse whorls ; aperture oblong, 3 fourths of it* 

 length. 



Da Costa p. 96. tab. 5. j~. "6X Turbo adversus. 



Shell half an inch long, a quarter broad, fometimes with a fe\V 

 longitudinal and tranfverfe -ridges ; the terminal whorls very 

 fmall. 



3g0. B. rivalis. Oval, pellucid, yellow horn-colour, with 

 4 or 5 reversed whorls tapering to a fine point : aper- 

 ture oval-oblong* 



