NOMENCl.ATURK. 
25 
BIVALVES. 
Ambitus. Circumference of the shell. 
Area. Slope. 
antica. Anterior slope or Area ; that side of the 
beaks or that space in which the ligament 
is situated. 
distincta. Distinct ; separated from the sides of 
the shell eitlier by a channel or a keel. 
inflexa. Inflex : having incurved lips. 
liter ala. Literate ; ornamented with characters 
like letters. 
postica seu Areola. Posterior slope; the other 
side of the beaks, 
marginata. Marginate; surrounded by an ele- 
vated margin. 
patula. Patulous ; the margins of the areola 
gaping, 
serrata. Serrate ; saw-like in the channel of the 
areola. 
Apices. Beaks; the tips or extreme parts of 
the umbones or bosses. 
