20 
BULLA. DIPPER . 
often a chesnut shade, and visible all the n ay down: length 
two inches or more; breadth one and a quarter. 
The animal is furnished with a strong gizzard, consisting 
of two somewhat triangular thin smooth white testaceous 
plates, nearly an inch in diameter, placed upon each other, 
with an intervening thick tough yellowish ligament con. 
necting them together : and within one of the lateral angles 
placed on the ligament, is an elongated testaceous semi- 
cylindrical hollow white additional plate. Fig. 3, 4. 
On the Devon and Cornish coasts 5 and Dublin bay. v.v. 
2. Bulla Hydatis. Paper Dipper. 
Montagu, Vignette 1. f. 1, 2— Da Costa , pi. 1. f. 10- 
Donovan , pi. 88-— Linn . Trans, ix. pi. 6 . f. 1— Dorset Cat. 
pi. 23. f. 10 . 
Shell oval, thin, brittle, semitransparent, tumid, green 
or yellowish, often covered with a thin chesnut-colored 
skin, irregularly wrinkled transversely, and very finely and 
closely striate longitudinally, when young glossy and newly 
smooth : aperture large, contracting near the crown, which 
is concave and without external volution: outcr-lip very 
thin and extending beyond the crown ; inner-lip spread,! 
little thickened, and whitish or chesnut-colored: lengths 
inch ; breadth three quarters. 
The inhabitant of this shell is also furnished with* 
strong coriaceous blackish gizzard, of a triangular form,t: 
consisting of three oval petal-like divisions, each with 2 
strong raised longitudinal rib down the middle, and about 
twelve transverse ones. Montagu, Vignette 1. f. 5 ,6. 
On the western coasts, Dunbar in Scotland, and the 
Strand at Balbriggan in Ireland, v. v , 
3. Bulla Ale era. Elastic Dipper . 
Dorset Cat. pi. 22. fig. 13. 
Bulla resiliens. Donovan, pi. 72. 
Shell oval, transparent, membranaceous, elastic, pale 
horn-color, often marked with brown spots or patches, 
slightly striate longitudinally, whitish within: aperture 
large, much contracted at top, which is obtuse,. convolute 
and channelled round the circumference, the volutions cd 
produced but flat and even with the body $ outer-lip ex- 
