Crested, bill moderate, strong, conic, entire, upper mandible rather the
longer and slightly curved, nostrils basal, rounded and concealed by
projecting feathers. Wings rather long, with the fourth and fifth
primaries usually longest, tail rather long, legs and feet robust, the
latter rather large, and provided with curved, strong and very sharp
claws. Prevailing color of all known American species, cinereous.
This genus comprises the crested species of Europe and America, which
were formerly included in the genus Parus, Linn., but which evidently
form a natural and easily characterized group, fully entitled to generic
distinction.