86 TYRANNIDA. 
Bugaba®, Calovevora® (Arcé), Lion Hill (M‘Leannan*), Chepo (Arcé).—SovuTH 
America, Ecuador !! and Bolivia °. 
A series of specimens of this Tyrant-Flycatcher from the northern part of its range 
when compared with a similar series of C. virens shows that these species are barely 
separable. The upper plumage, however, of C. richardsoni is slightly less olivaceous 
than that of C. virens; the chest is more continuously and distinctly cinereous and the 
abdomen scarcely tinged with yellow. When, however, we come to the migratory 
flocks which spread southward at the approach of winter and distribute themselves 
throughout Mexico and Central America, we find the greatest difficulty in discrimi- . 
nating between these two birds. In naming our specimens we have been governed a 
good deal by their geographical distribution, and we believe that the western 
form in winter spreads over the greater part of Mexico, Guatemala, Costa Rica, and 
Panama, and thence southwards as far as Bolivia. The only point where the two 
birds come into contact as shown by our specimens is in the North Mexican State 
of Nuevo Leon, whence Mr. Armstrong has recently sent us specimens which must 
certainly be referred to C. virens, while others are almost as certainly referable to 
C. richardsoni. 
In general appearance C. richardsoni is also exceedingly like C. brachytarsus ; but the 
latter may be distinguished by its shorter and more rounded wing, the first primary 
hardly exceeding the fifth in length. In C. richardsoni it is obviously longer. 
We are in some doubt whether C. plebeius applies to this species or to C. brachy- 
tarsus, and the question cannot be settled without an examination of the types, which 
are said to have come from Mexico”. The measurement of the wing points rather to 
the latter bird. “ 
The writings of North-American ornithologists give full details concerning this bird, 
and from them we gather that its breeding-range comprises a vast area extending from 
Arizona and Texas to the Great Slave Lake. The nest is described as constructed 
chiefly of plant-fibres, sometimes, though rarely, ornamented with lichens and secured 
in the fork of a branch of a tree. The eggs are like those of C. virens. 
8. Contopus brachytarsus. 
Empidonaz brachytarsus, Scl. Ibis, 1859, p. 441"; Lawr. Ann. Lyc. N. Y. vii. p. 8272. 
Contopus brachytarsus, Salv. Ibis, 1861, p. 354° ; P. Z. 8.1870, p.199*; Scl. & Salv. P. Z. S. 1864, 
p- 860°; Ridgw. Man. N. Am. B. p. 339°, x. p. 589"; Sel. Cat, Birds Brit. Mus. xiv. 
p- 240°. 
Contopus schotti, Lawr. Ann. Lyc. N. Y. ix. p. 202°; Ridgw. Pr. U. S. Nat. Mus. viii. p. 571”. 
Contopus depressirostris, Ridgw. Pr. U. S. Nat. Mus. vi. p. 403”. 
C. virenti quoque similis, sed minor, alis magis rotundatis, remige primo quinto fere quali haud longiore ut 
videtur distinguendus. (Descr. feminz exempl. typ. ex Cordova, Mexico. Mus. Brit.) 
Hab. Mexico, Cordova, Santecomapan (Sallé!), Teapa (Mrs. H. H. Smith), Merida in 
