THE GUANS. 245 
general colour of upper-parts and chest, greyish-olive ; breast 
and belly white; uader tail-coverts rufous-buff ; tail-feathers 
tipped with buff. Total length, 25 inches; wing, 9°6; tail, 
10°8 ; tarsus, 2°8 ; middle toe and claw, 2°8. 
Range.—Mexico ; Rio Armeria, Rio Tupila, Real Arriba, 
Vera Cruz, Oaxaca, and Tehuantepec. 
XIII. THE LESSER GREY-HEADED GUAN. ORTALIS VETULA. 
Fenelope vetula, Wagler, Isis, 1830, p. 1112. 
Ortalida vetuéa, Wagler, Isis, 1832, p. 1227. 
Ortalida maccalli, Baird, B. N. Amer. p. 611 (1860). 
Orialda plumbiceps, G. R. Gray, List Gallinee Brit. Mus. p. 11 
(1867). 
Ortalida rujicrissa, Sclater and Salvin, P. Z. S. 1870, p. 538. 
Ortalis vetula, Boucard, P. Z. S. 1883, p. 460; Ogilvie-Grant, 
Gat. 6. Brit. Mus. xxii. p. 512° (1893). 
Ortalis vetula maccah, Coues; Bendire, N. Am. B. p. 1109, 
pl. iii. fig. 16 [Egg] (1892). 
Ortalis vetula pallidiventris, Ridgway, Man. N. Am. B. p. 209 
(1887). 
Adult Male and Female.— Differs from O. poliocepha/a in being 
much smaller, and in having the head and neck less grey. 
Total length, 20 inches ; wing, 8; tail, 9°6; tarsus, 2°5 ; middle 
toe and claw, 2°5. 
This species varies somewhat in colour in the different parts 
of its wide range, especially on the under-parts of the body, 
but from the very large series of specimens examined it is clear 
that all are merely climatic varieties of one form. 
Range.—Southern Texas, extending through Eastern Mexico 
and Central America to the United States of Colombia. 
Habits.—Assistant-Surgeon James C. Merrill, U.S. Army, in 
his notes on the “ Ornithology of Southern Texas,” writes as 
follows:—“ The ‘Chachalac,’ as the present species is called 
on the Lower Rio Grande, is one of the most characteristic 
birds of that region. Rarely seen any distance from woods or 
