8 TYRANNIDA. 
1. Rhynchocyclus brevirostris. 
Cyclorhynchus brevirostris, Cab. in Wiegm. Arch. f. Naturg. 1847, i. p. 249°; Scl. P. Z. S. 1856, 
p. 296°; Scl. & Salv. Ibis, 1860, p. 399°. 
Rhynchocyclus brevirostris, Cab. & Heine, Mus. Hein. ii. p. 57°; Salv. P. Z. 8. 1867, p. 148°, 1870, 
p. 197°; Scl. Cat. Birds Brit. Mus. xiv. p. 1667. 
Rhynchocyclus mesorhynchus, Cab. J. £. Orn. 1865, p. 414°. 
Rhynchocyclus griseimentalis, Lawr. Ann. Lyc. N. Y. ix. p. 112°; Salv. Ibis, 1869, p. 315"; 
v. Frantz. J. f. Orn. 1869, p. 307”. 
Supra olivaceus unicolor; alis et cauda nigricantibus extrorsum olivaceo limbatis; oculorum ambitu griseo, 
ciliis albis: subtus dilutior, griseo vix tinctus; ventre medio flavo; subalaribus flavo albicantibus: rostri 
maxilla nigra, mandibula albicante ; pedibus corylinis. Long. tota 6:0, ale 3:1, caude 2°75, tarsi 0°75, 
rostri a rictu 0-7. (Descr. maris ex Choctum, Guatemala. Mus. nostr.) 
© mari similis, sed pogonio externo remigis primi levi nec aspero. 
Hab. Mexico, Jalapa* (M. Trujillo), Cordova (Sallé*); Guatemaua §, Choctum 3 (0. 8. 
& HF. D. G.), La Trinidad, Volcan de Fuego (0. 8.); Costa Rica 1! (Carmiol © & 
Endres), Dota (Carmiol®), Trazu (Rogers); Panama, Volcan de Chiriqui ®, Bugaba &, 
Calovevora °, Santa Fé > (Arcé). 
Rhynchocyclus brevirostris is the Mexican and Central-American representative of a 
small section of the genus containing three closely allied members. The oldest known, 
ft. olivaceus, is an inhabitant of the forests of South-eastern Brazil; R. wquinoctialis 
occupies the eastern forests of the Andes of Equador and enters our fauna as far north 
as the line of the Panama Railway ; the present species then takes its place and spreads 
northwards as far as the forest-clad slopes of the mountains of the Mexican State of 
Vera Cruz. Another more remotely allied form, F. fulvipectus, occupies Western 
Ecuador and the Cauca valley of Colombia. 
Several attempts have been made to divide R&. brevirostris: thus, the Guatemalan 
bird was named fi. mesorhynchus by Prof. Cabanis and the Costa Rican R. griseimen- 
talis by Mr. Lawrence. The latter ornithologist correctly showed that the size of the 
bill, relied on for the discrimination of &. mesorhynchus, is a very unstable character ®, 
but the peculiarities of coloration set forth as distinguishing 2. griseimentalis do not 
hold good when a series is examined. This is also Mr. Sclater’s view’, who confirms 
Salvin’s note on this subject ® We do not, however, subscribe to Mr. Sclater’s state- 
ment that BR. brevirostris and R. equinoctialis gradually merge into one another. The 
differences are, it is true, very slight, but we have no difficulty in assigning every 
specimen before us to its proper place, and their geographical boundaries appear to 
be quite definite. 
h. brevirostris is a native of the forests of the hotter parts of the countries it inhabits. 
In Mexico it occurs near Jalapa at an elevation of about 4000 feet. In Guatemala we 
found it in the forests near Choctum, at an elevation of about 1200 feet above the sea, 
and on the slopes of the Volcan de Fuego as high as 3000 feet. It probably has a 
