BULLA. . DIPPER . 
2 3 
crown, without external volutions : aperture very narrow, 
reaching the whole length of the shell, dilated into an oval 
at the base: resembles the last, .but is not so cylindrical, 
and the length, which is about a quarter of jin inch, is 
double its breadth. 
Western coasts, Scotland, and Dublin bay. v. v. 
9. Bulla retusa. Truncate Dipper . 
Bulla truncata. Montagu , pi. / . f. 5— Linn. Trans, v. 
pi. 1. f. 1,2— Walker, f. 62. 
Shell somewhat cylindrical, white, rather opake, finely 
and regularly striate longitudinally on the upper half only, 
the lower part being nearly smooth : crown abrupt, with a 
large perforation in which the volutions arc visible : aper¬ 
ture reaching the whole length of the shell, very narrow, 
something contracted about the middle and dilated into an 
.oval at the base, where the outer-lip is a little spread over 
the pillar: length hardly two lines ; breadth more than half 
as much. ‘ , 
Western coasts, Dublin bay, and North Britain, v. v. 
10. Bulla obtusa. Obtuse Dipper. 
Montagu, pi. 7- f. 3— Dorset Cat. pi. 18. f. 14— Walker , 
Ji 61 . 
Shell &me\vhat cylindrical, opake, white or covered with 
a chesnut-^rovvn skin, longitudinally wrinkled ; crown ob¬ 
tuse, with four or five very slightly produced volutions: 
aperture extending nearly hut not quite to the whole length 
of the shell, narrow, a little compressed in the middle, and 
dilated into an\>val at the base; iuner-lip thickened, smooth, 
white: lecgthVbout two-tenths of an inch; breadth half its 
'fezgth. 
Walker's figure is an excellent representation of this 
shell: butltfr. Jacobs! who furnished the author with the 
descriptions, mistaking it for aVoluta, it has hitherto been 
quoted for the V. alba, to which it has no resemblance. 
Western coasts, Dublin bay, and Scotland, v. m. 
* 31. Bulla aperta. Wide Dipper. 
Bit Costa , ul. 2. f. 3— Montagu, Vignette 2. f. 1— Dono - 
ran, pi. 120. f. 1— Dorset Cat. pi. 22."f. 3. 
( Shell somewhat orbicular, extremely thin and brittle, 
transparent. 
