_Psittaca borbonica torquata_ Briss., Orn. IV p. 328, pl. XXVII f. 1
(1760). (Bourbon.)
_Psittacus alexandri var._ [gamma] Linnaeus, S.N. p. 142 (1766).
_Perruche à collier de l'Isle de Bourbon_ Daubenton, Pl. enl. 215.
_Perruche à double collier_ Buff., Hist. Nat. Ois. VI, p. 143 (1779).
_Alexandrine Parrakeet var. C. Double Ringed Parrakeet_ Latham, Syn. I
p. 326 (1781).
_Psittacus eques_ Boddaert, Tabl. Pl. Enl. p. 13 (1783).
_Psittacus semirostris_ Hermann, Obs. Zool. p. 125 (1804).
_Psittacus bitorquatus_ Kuhl, Consp. Psitt. p. 92 (1820).
Rose Ringed Parrakeet var. B. Latham, Gen. Hist. II p. 161 (1822).
_Psittacus bicollaris_ Vieillot, Enc. Meth. III p. 1385 (1823).
_Palaeornis bitorquatus_ Vigors, Zool. Journ. II p. 51 (1825).
_Palaeornis borbonicus_ Bp., Rev. and Mag. Zool. 1854, p. 152. No. 140.
There has been considerable confusion with regard to this parrot. It was
first asserted that it occurred on both Bourbon and Mauritius. Then
Professor Newton separated the Mauritius bird as _Pal. echo_. Salvadori,
however, in Cat. Birds Brit. Mus. XX, p. 442, reunited the Bourbon and
Mauritius birds, while quite unaccountably stating only Mauritius as the
habitat.
The Abbé Dubois describes this bird as follows: "Green Parrots as large as
pigeons having a black collar."
Now the species of _Palaeornis_ from Rodriguez, the Seychelles, and the
mainland of Africa are all distinct, and the other land birds of Mauritius
are and were different from those of Bourbon. I therefore feel quite
certain that Professor Newton is right, and that his _Palaeornis echo_ is
distinct from _P. eques_, though, unfortunately, we do not know in which
way the two forms differed.