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A very fair stage road extends from Chililaya to La Paz, a 
distance of 45 miles over a high, rolling plateau and here as else- 
where all the arable land is well cultivated, with ditches for 
irrigating wherever water is to be obtained. Large areas are so 
gravelly and rocky as to be quite unfit for cultivation, yet over 
many square miles of such ground the larger boulders have been 
thrown up into heaps, each containing many tons ; these in places 
are so abundant that the piles seem to occupy the greater part of 
the surface. It is scarcely evident at the present day for what 
purpose such an immense amount of work has ever been done. 
The scanty vegetation that at present exists, consists largely of 
scattered tufts of grass, two or three cespitose species of cactus, 
and a few shrubby composites. 
The city of La Paz is in a great gulch some 1,000 feet lower 
than Lake Titicaca and about twice that distance below the sur- 
rounding plateau. The Azcalyptus is the commonest tree in 
cultivation, several fine groves standing out conspicuously as one 
ooks down upon the town. Another much smaller tree in some 
of the gardens with handsome purplish flowers is a Cantua, 
apparently the species /axifolta. Tall, branching, cylindrical 
jointed cactuses are common as a hedge plant along various 
lanes and in the lower part of the town a weeping willow grows 
nely. 
From La Paz we went with mules to Sorata, the trail passing 
around the northwest base of the Sorata range, over a pass some 
14,000 feet elevation and down quite rapidly 6,500 feet to the 
town of Sorata. Some time before reaching the summit of this 
pass, known as the Huillata, 1 obtained specimens of a tree 
growing at the highest elevation of any collected on the trip, 
about 13,000 feet. The species proves to be a Buddleia of the 
family Loganiaceae and was growing to a height of 20 feet with a 
broad, rounded top and a trunk 18 inches in diameter. Only 
two or three individuals were noted and they were evidently 
not natives of the region. Sorata, being 4,000 feet lower than 
a Paz, has a most agreeable climate the year round. Here, as 
in the latter town, Eucalyptus trees were the most conspicuous 
of any, but various other species were quite common, especially 
