The Kagu (Rhinochaetus jubatus).

Artist Albin Mesnel (painter) Felix-Jean Gauchard (engraver)
Title
English: A pair of kagou birds (Rhynochetos jubatus) with one displaying to the other.
Description
Wood engraving by Gauchard after Mesnel.
Medium Wood engraving
Source: https://commons.wikimedia.org/wiki/File:A_pair_of_kagou_birds_(Rhinochaetus_jubatus)_with_one_displa_Wellcome_V0022346.jpg

The kagu or cagou (Rhynochetos jubatus) is a crested, long-legged, and bluish-grey bird endemic to the dense mountain forests of New Caledonia. Rhynochetos jubatus is the only surviving member of the genus Rhynochetos and the family Rhynochetidae.