Cf. Sclater, Cat. Birds Brit. Mus. xiv. 1888, p. 282.
P. buckleyi has curious long filaments on the head of the young. Sclater and Salvin, P.Z.S. 1880, p. 158.
Cat. Birds Brit. Mus. xiv. 1888, p. 326.
Cat. Birds Brit. Mus. xv. 1890, p. 3.
I.e. interiorly scutellated at the back.