(Procellariidae; Ϯ MacGillivray's Petrel P. macgillivrayi) Gr. ψευδος pseudos false; genus Bulweria Bonaparte, 1843, petrel; "It is perhaps unfortunate that this bird was placed in the genus Bulweria, as its significance has thereby been lost. ... The tail of macgillivrayi is shorter than the tail of Bulweria, although the bird is larger. In the former the first primary is shorter than the second, while in Bulweria the first primary is the longest. The difference can be considered of generic importance, so I introduce PSEUDOBULWERIA, gen. nov.; type, T. MACGILLIVRAYI Gray. In Bulweria the wing measurement is less than twice the tail measurement; in Pseudobulweria the wing measurement is more than twice that of the tail" (Mathews 1936).