[14]

H. Gadow, Bronn's Thier-Reich, Aves, Syst. Theil. 1893, p. 90.

[15]

H. Gadow, Bronn's Thier-Reich, Aves, Syst. Theil. 1893, p. 90.

[16]

A pygostyle is occasionally found in Struthio and Apteryx.

[17]

P. L. Sclater, P.Z.S. 1895, p. 401.

[18]

Argentine Ornithology, ii. 1889, p. 220.