BIRDS FROM COSTA RICA—WETMORE 29 
mountain was heavily forested so that I marked the old, obscure 
trail along the ridges, making it possible to work in here without 
difficulty on days when the mountain slopes were hidden im fog and 
mist. 
From the house a reasonably good trail led around to the east to a 
broad, fairly level area known as Los Cuadros, where there were old 
plantations and overgrown clearings in a fine forest in which the larger 
trees rose to a height of 60 meters. Below the forest the land was 
rolling, with the ridges and slopes in pasture (pl. 5, fig. 2), while 
depressions and gullies were filled with brush and stands of oaks and 
other trees. This was excellent bird country, but a little lower down, 
where the forest was again continuous for some distance, there was 
a dense undergrowth of bamboo that was silent and lifeless and 
extremely difficult to penetrate. The head of the Rio Liberia swings 
into a deep, wooded valley at the north of the house, with tributaries 
of clear water flowing toward it at frequent intervals. Los Cuadros 
marked the divide with the Caribbean slope, and here water ran 
toward the east. When I climbed to open slopes on the mountain 
shoulders that from below appeared covered with smooth turf I 
found often that they were waist high in dense grass and tough bushes 
and almost impassable. In the forest there was necessity for much 
use of the machete. The undergrowth was always wet and the 
slopes often slippery. 
The bird life here was interesting and abundant, and after long 
trips afield it was most agreeable to work at the hacienda in the cool, 
pleasant afternoons, with macaws flying about, a house wren singing, 
and howler monkeys roaring in the distance. Don Fernando Siles, 
manager of the hacienda, and his wife were most kind to me in every 
way, and it was with definite regret that on November 16 I saw my 
outfit loaded on pack mules for the journey back to Liberia. I had 
2 more days in the field here, and then on November 19 Aguilar and I 
returned by plane to San José. On November 23, accompanied by 
Dr. Valerio and Aguilar, I descended again by rail to Puerto Limén, 
to sail at 6 in the evening on the United Fruit Line steamer Veragua. 
LIFE ZONES AND DISTRIBUTION 
Since the period of work in Guanacaste was short, my investiga- 
tions were in the nature of a reconnaissance that permitted only 
partial view of the region. I have therefore restricted the extent of 
the present discussion of distributional data. The area about Liberia 
lies in the arid division of the Lower Tropical Zone, this extending 
inland over the lower slopes of the mountain through the area drain- 
ing into the Pacific. Birds were common here and in good variety, 
though the species are definitely fewer than in corresponding areas 
