Chocaya. 
A tin mine on the Bolivian Hailway,in Dept.of Potosi, 
far south of Tjyuni,and about 23o kiloraeters north of the 
Argentine frontier. ihie mine itself is at 13,100 feet, 
in a valley running back, west from thr R.R. At the 
head of this valley are peaks rising to 15,000 feet. 
The R.R.Station^ is at 12,500 feet. The v/hole surroundin 4 , 
country is very arid and barren,especially in the valley. 
A small river runs past the R.R.Station,whic eventually 
finds its way into the Rio Pilcomayo. The country rises 
rather steeply to the west of the river (it flov/s nearly 
north and south) up to the altiplano.whilg to east of rivl 
er the country is rather flat,but cutinnumerable 
small ravine,with precipituous sides. The flates between 
the ravines are rather thickly overgrown with low thorn- 
bush and small cacti,and the earth thickly strewn with 
small loose stones. Most of the water in this valley, 
including,the river,is slightly saline and unfit to drinkl 
There is a fine spring of fresh water a couple of miles a 
above Chocaya Station,from which water is carried in larg 
cans to the mine for drinking purposes. Birds were scarce! 
in the valley and of few species. Here we took for the 
first time Geositta frebeni .a very pale,desert form,but 
quite different from the allied species. Phyrgilus 
atriceps ; Sicalis aureiventris and Lentasthenura aegithal- 
Pides “^e rlepschi were most common. Akh Jr'silopsiagon 
orbignyi . Asthenes roodesta _. Muscisaxicola capis - 
t rata . Phyrgilus p. plebe.ius and the white breasted 
Purnariidae were also present. Po others seen. 
. Around the mine mills at Sta.Ana,there was almost no 
vegetation,not even bunch grass,with slopes steep and 
badly eroded in places. Lack of vegetation probably due 
largely to the smoke from.the reduction plant. Higher up 
the ia±K valley at the mine and above on the plateau 
conditions were better,but species were few and individ¬ 
uals scarce,except for a few forms,such as Sicalis 
aureiventris . Asthene s modestus a nd the White Breasted 
Purnariidae. Hov/ever,up on the plateau to the south of 
the mine camp we found Tinarootes pentlandi . First I found 
a flock of about seven birds,and later a pair with four 
half grown youhng were secured. Apparently their sole foo 
consists of the young,tender leaves of a low,small-leaved 
dark green bush. The crops all birds taken were gorged 
with these leaves,which were quite dry. Evidently the 
biPds must subsequently drink water in order to digest 
them. The birds are fast fliers,and get up with a cacklin 
• te,rather disconcerting to the gunner. After flushing 
once,like all Tinamous, they prefer to hide or. run,and 
are equally adept at both performances,their protective 
coloration making them practically invisible a short 
distance away. A pecu3,iar Gopher-like animal was secured 
in the valley,where they burrow in the soft sand of the 
