GLOSSARY. Ill 
R. 
radiata, rayed. 
radidtulus, slightly rayed. 
reflécted, bent back. 
reticulated, like network. 
reveléta, unveiled, discovered. 
ringens, grinning like a dog, z.e. showing the teeth. 
rivicola, an inhabitant of streams. 
roseo-labidta, having a pink-coloured lip. 
roseum, pink. 
rostrata, beaked. 
rotunda, round. 
rotunddta, rounded. 
ruféscens, reddish. 
rujilabris, having red lips. 
rugosa, wrinkled. 
rupéstris, inhabiting cliffs. 
S. 
scdlariformis, formed like a Scalaria (a spiral sea shell 
with projecting ribs which give the appearance of the 
divisions of a ladder, scala). 
scar. ‘‘ Muscular scars” are the depressions formed by 
the attachment of the muscles holding the parts of a 
bivalve shell together. 
scutulum, a small shield. 
secdle, a grain of rye. 
séptum (plural sépta), a division. 
sericea, silky. 
séssile, situated on a flat surface, not raised on a stalk. 
shagreéned, covered with small granules. 
