102 GLOSSARY. 
antérior, the front; applied to bivalves, the large or blunt end. 
antivertigo, not reversed. 
aperture, an opening; of univalves the mouth. 
dpex, the extreme point of the spire of a univalve. 
aquatic, inhabiting water. 
arborum, inhabiting trees. 
arbustorum, inhabiting copses. 
Arion. A fabled musician. The name of a genus. 
aspérsa, spotted, sprinkled, 
ater, black. 
atro-purpurea, dark purple. 
auriculdria, ear-shaped. 
dis, applied to univalve shells, the centre column formed 
by the junction of the whorls. 
B. 
Balia, striped. 
beak, see wmbo. 
bidentata, having two teeth. 
bigrandta, having two small teeth. 
bilibed, divided into two rounded parts. 
biplicdta, having two folds, 
bivalve, applied to shells with two movable plates forming 
the sides. 
bizbna, with two bands. 
branchial, pertaining to the gills. 
Bilimus (deriv. disputed), the name of a genus. 
Burnétit, after Burnet. 
byssus, strands by which D. polymorpha, &c., attach them- 
selves to stones. 
Bythinia. An ancient province of Asia Minor; the name © 
of a genus. 
