24 
BULLA. DIPPER. 
transparent, clear white, irregularly wrinkled transversely 
but glossy on the outside, almost entirely open, rounded 
and dilated at the base, a little narrowed at the crown 
which has a slight indenture; outer-lip extending beyond 
the crown; inner-lip slightly turned in, rendering the pillar 
or involution quite visible to the end: length more than 
half an inch ; breadth rather less. 
The animal also possesses a gizzard something resem¬ 
bling that of the B. lignaria, hut it is of a more regularly 
triangular form, with the base elongated; and the supple¬ 
mental plate, which is placed within the base of the trian¬ 
gular ones, is of a lozenge shape, or quadrangular, with tbs 
points of two of the angles elongated. Fig. 5, 6. 
Western coasts, Dublin bay, Scotland, v. v. 
12. Bulla Catena. Chain Dipper. 
Montagu, pi. 7-fig-7• 
Bulla punctata. Linn. Trans, v. pi. 1. f. 6 , 7j 8 . 
Shell somewhat oval, white, transparent, glossy, with 
numerous fine transverse striaj which run rather obliquely 
and with the assistance of a magnifier seem to be connect¬ 
ed and interwoven in a chain-like manner: aperture very 
large, almost entirely open like B. aperta, but closing a: 
the crown, which is obtuse and turned in so as to form i 
single volution; inside glossy, the pillar-lip a little spreai; 
length about the tenth of an inch j breadth not so much 
Variety , with a more transparent single zone round it, 
taking in eight or ten of the chain-like striae, the other 
parts appearing frosted and not so glossy; the crowns 
little concave, and the outer margin of the aperture close 
to the body reflecting a little and forming a depression oa 
that part. 
Western coasts, and North Britain : rare. v. w. 
1.3. Bulla haliotoidea. Ear-shaped Dipper. 
Montagu, pi. 7- f- 6 —Dorset Cat. pi. 22. f. 5*. 
Shell somewhat oval, white, extremely thin, transparent, 
very slightly wrinkled on the outside : aperture broad ova!, 
not quite extending to the crown, which is small, obtuse, 
and twisted sideways into about two volutions: inner-lipi 
little turned in ; the inside visible to the end. It differs 
from 
