Pseudibis Hodgs., Zool. Misc. (Gray), p. 86 (1844).
Type by mon., Ibis papillosus Ruppell.
In this genus the head and nape only are naked in the adults ; the bill is more slender than in Threskiornis, the feet shorter and the plumage principally black instead of white; the inner secondaries are normal in shape and neither lengthened nor disintegrated and there are no long neck-plumes in the breeding-season.
Sharpe, in the Catalogue of Birds, divided Inocotis (=Pseudibis) into two genera, making davisoni the type of his genus Graphtocephalus, which he separated from Inocotis because of its smooth crown. This, however, seems to me to be only a matter of degree, for an examination of the crown of davisoni shows most distinctly small carunculations everywhere, though not projecting into small spicules or papillae as in papillosus. In all other respects the two forms seem quite congeneric, whilst in plumage they are identical. It is even doubtful whether they should not be treated as geographical subspecies of the same species.
Key to Species,
A. Papillae of crown and nape much developed and red in colour………………P. papillosus, p. 316.
B. Papillae of head obsolete and not coloured red………………P. davisoni, p. 317.