BULLA. DIPPER. 
27 
Shell oblong, taper, transparent, glossy, smooth, horn- 
color, with five or six reversed pointed volutions, the first 
half as long as the shell: aperture narrow-oval, spreading 
a little at the base; outer-lip very tiling inner-lip a little 
thickened and slightly indented. It differs from B. fonti¬ 
nalis, in being more taper and produced, in having the 
aperture more narrow and contracted, and in its darker 
color: length half an inch ; breadth not a quarter. 
Stagnant waters, and slow streams, v. v . 
§ 21. Bulla fluviatilis. Rivulet Dipper. 
Helix Bulkeoides. Donovan , pi. 168. f. 2. 
Shell oval, smooth, glossy, brittle, liorn-color, with two 
reversed volutions which are hardly raised or . extending 
beyond the body of the shell: aperture oval-oblong, nearly 
as long as the body volution : length a quarter of an inch ; 
breadth three tenths. 
Two specimens of this rare shell were found, by Captain 
Brown, in a stream near Clonoony Barracks, in Ireland, by 
which we are enabled to clear up the doubts which have as 
yet existed respecting this very obscure species. In every 
respect they corresponded with the shell figured by Dono¬ 
van. They were undoubtedly full grown, and both in the 
number of volutions, and other specific marks, materially 
differed from B. fontinalis. And we cannot but concur with 
this respectable conchologist, that it has no more reason 
to be placed among the Helices, than Bulla fontinalis, 
Hypnorum, or rivalis, v. m. 
22. Bulla emargjnata. 
Lmn. Trans, v. pi. 1. f. 9, 10, 11. 
Shell gibbous, transparent, smooth, with the aperture 
notched, and the.lip slightly arched. 
On the Pembrokeshire coast: minute. 
23. Bulla denticulata. 
Linn. Trans, v. pi. 1. f. 3, 4, 5. 
Shell oblong, smooth, white, transparent, obtuse, nearly 
equal: aperture with a very sharp tooth at the top. 
On the Pembrokeshire coast: minute. 
a, 
(h 
1)2 
CARDIUM. 
