CHAP. XVI RESIDENCE AT TARAPOTO 95 
first expedition to the Campana Mountain and 
Lirio-pampa, already described at some length. 
In February 1856, he made an excursion to the 
head of the Puca-yacu, on the western slopes of 
Mount Guayrapurima. 
In March he went to the Upper gorges of the 
Shillicaio river. 
In May he went to the top of Cerro Pelado, and 
to the upper gorges of the Aguashiyacu, Uchulla- 
yacu, etc. There are a few notes on Mount Pelado, 
which consists of bare sharp ridges running about 
S.E. and N.W., the N.E. side being very pre- 
cipitous but sloping more gradually towards the 
plain of Tarapoto. The rocks are covered with 
lichens, a few ferns, some rigid-leaved Liliaceae, and 
a few dwarf shrubs. From the S.E. the ridges dip 
abruptly to deep ravines, which form the sources 
of the streams of the pampa, as well as of some 
tributaries of the Huallaga. Lower down the 
slopes are clad with low forest which is densely 
mossy. The summit of all the ridges is a white, 
friable, coarse-grained sandstone, in thin layers, 
inclined at a very high angle. The Cumbasa rises 
to the north of this group of mountains, and many 
of the deep ravines above mentioned are some of 
its tributaries. 
(The accompanying beautiful drawing of the 
mountains north of Tarapoto is the only one of 
large size which was carefully shaded by Spruce 
himself. With the one exception of the immediate 
rough bit of foreground, it has been photographed 
from the drawing as he left it fifty years ago. The 
curiously ridged mountain to the right exactly cor- 
responds to his description of it above given ; and 
