d2. Smaller. Fassinans rhomboidea.
c2. More ovate, tapering behind. Fassinans.
b2. Rays distinct, well developed over most of the disk. Ground color of epidermis lighter. Bigbyensis.
a2. Moderately convex, dia. 40–49 per cent of length. Barnesiana typica.
b1. Beaks not elevated, shape trapezoidal, rhomboid, or subovate.
c1. Dia. about 41 or 42 per cent; size small.
d1. Shape somewhat elongate (trapezoidal); rays obscure. Barnesianus.
d2. Shape shorter (rhomboidal).
e1. Rays obscure. Lenticularis.
e2. Rays present, color of epidermis lighter.