218 ‘ MYAs 
within, varied with green ; no cavity under the 
beak. Dimensions two and a half inches by 
one and two thirds. 
evata, shell but middling, subovate, convex, not 
remarkably thick, horn-colour, not radiated, 
flattened and fuscous on the anterior margin ; 
beaks decorticated and placed nearer central ; 
boss prominent ; pearly within ; cavity of the 
beak capacious ; primary teeth very oblique, 
almost parallel to the posterior margin and 
much compressed. Dimensions four inches by 
three. 
cariosa, shell but middling thick, long forward. 
short back of the beaks ; olive-green, sometimes 
radiated with green and with interrupted wrink- 
les in longitudinal rews ; beaks somewhat pro- 
minent, distant, carious, wax-yellow beneath the 
epideriils concavity bluish-white ; teeth often 
subconic and crenate. Dimensions two inches 
and a quarter by one and a half. 
achrocea, shell thin, fragile, translucent, subovate ; 
hinge margin straitish ; pale-olive or orange : 
often with. green wrinkled radii 5 anterior mar- 
gin wrinkled ; beaks decorticated and near, 
with two or three concentric undulations ; bluish- 
white or yellowish within, reddish near the 
base ; teeth very oblique and much compressed. 
Dimensions an inch and a quarter by an inch 
and three quarters. 
nasuta, shell thin, oblong, compressed, beaked, 
hora-colour or fuscous, wrinkled, with green 
radiations ; bluish-white within ; teeth crenaic ; 
scarcely any back-cavity. Dimensions about 
one inch by two and a half. 
