J. G.Keulemans HitK. Hanha rt
Pig. 1 . TURD U S G RA Y II.
I 2. „ ■ CASIUS
TURDUS GRAYI, Bp.
GRAY’S THRUSH.
Turdus helvolus, Licht. Preis-Verz. Mex. Yog. no. 85 (1830); id. Nomen cl. Av. Mus. Berol,
p. 26 (1854).
Turdus grayi, Bp. P. Z. S. 1837, p. 118; Salvin & Godman, Biol. Centr.-Amer., Aves, i. p. 18
(1879); Seebohm, Cat. Birds Brit. Mus. v. p. 219 (1881).
Planesticus grayi, Bp. C. R. xxxviii. p. 4 (1854).
Planesticus luridus, Bp. C. R. xxxviii. p. 4 (1854).
Planesticus casius, Bp. C. R. xli. p. 657 (1855).
Turdus tristis (nec Swains.), Sclater, P. Z. S. 1856, p. 294.
Turdus casius, Sclater, P. Z. S. 1859, p. 330; Seebohm, Cat. Birds Brit. Mus. v. p. 220 (1881).
Turdus casius, Gray, Hand-1. B. i. p. 257, no. 3744 (1869).
Turdus luridus, Scl. & Salv. Nomencl. Ay. Neotr. p. 2 (1873).
Merula grayi, Ridgway, Proc. U.S. Nat. Mus. v. p. 494 (1883).
Merula tamaulipensis, Nelson, Auk, xiv. p. 75 (1897).
T. plag& alba gulari null&: pedibus brunneis, mini me flavis: subcaudalibus cervinis, abdomine concoloribus.
G ra y s T h ru sh is a common species throughout Central America from Mexico to Panama, ranging
also into Colombia. The typical examples came from Guatemala, where they were obtained by
Colonel Velasquez (Bp. P. Z. S. 1837, p. 118). Specimens had previously been procured in the
vicinity of Jalapa by the German travellers Deppe and Schiede, and these were named by Lichtenstein
Turdus helvolus (I. c. ) ; but as he never gave any diagnosis of the Mexican form, his name cannot be
employed for the species. Subsequently Bonaparte described (I. c.) his Planesticus casius from
Panama on account of its greyer tint, and yet a third form was characterized by him as P. luridus
from Colombia (I. c.).
Seebohm united the last-named species with the true T. grayi, which ranged, according to his
conclusions, from Mexico, through Central America to Colombia (Cat. Birds Brit. Mus. v. p. 219) ;
but he recognized T. casius as a distinct form, differing in “ having the upper parts russet-brown
instead of olive-brown,” and he regarded it as “ a local race, which has become partially differentiated
from its near ally in Panama ” (t. c. p. 220). The material at his disposal in 1881 was so small
compared with that which we now possess in the British Museum, that there is no doubt that if he
had examined the specimens at present in the Salvin-Godman Collection, he would have entirely
changed his opinion. He appears, however, not to have sufficiently weighed the wise opinion given
by Messrs. Salvin and Godman in the ‘ Biologiaj’ where the impossibility of recognizing T. casius
and T. luridus was clearly pointed out.
I should be far from insisting that there is no variation in the colour of Turdus grayi in the
various parts of its range, and 1 think that, in a few isolated localities, the birds of the forest districts,
where they may be permanent residents, are darker in tone than those of the low country; but the
characters given by Seebohm for the separation of the two races into T. grayi and T. casius are due
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