This genus contains a group of rather large Titmouses with black and yellow plumage, structurally close to the genus Parus but with long pointed crests. Like Parus, however, the birds of this genus have a broad ventral band and graduated tails.
Key to Species and Subspecies.
A. Forehead bright yellow.
a. Paler and brighter, green of back
more yellow and less olive M. spilonotus spilonotus, p. 89.
b. Darker, green of back more olive,
less yellow and with more black
in proportion M. s. subviridis, p. 90.
B. Forehead black.
c. Paler and brighter, tips of wing- [p. 90,
coverts yellow M. xanthogenys xanthogenys,
d. Darker and duller, tips of wing-
coverts white M. x. aplonotus, p. 91.