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kinds were carried on for ten days. The gravelly slopes leading 
out from the cafions were found to beara large Echinocactus, 
several species of Opuntia, a Cercus, Olneya and Covillea, while 
a Mammillaria was widely distributed over the slopes. Living 
specimens of many of these were obtained for the Garden. An 
ascent was made of the main peak and several minor elevations, 
and the entire range was traversed through a pass leading to the 
westward. In addition to the large amount of material repre- 
senting the plants and animals secured, observations of the topo- 
graphical features of the country resulted in adding materially to 
our knowledge of this region and a sketch map is being prepared 
by Mr. G. Sykes as a contribution to the geography of the 
country examined. 
The Hardy river was followed from this point to its head in 
Volcano Lake, and we arrived at acamp near this body of water 
on April 16. Volcano Lake is a sheet of water ten to fifteen miles 
in length and of half that width, very shallow and exists only in 
periods of high water. Into it pours the water of the Paredones 
channel which leaves the Colorado River a few miles below the 
international boundary. The drainage here is too complicated 
to be comprised in a brief description, but it may be said how- 
ver that some of the water of this lake finds its way into the 
Pescadora River, which is also a flood channel, some into the 
ns 2 three different outlets and some into New River which 
pours its waters over the international boundary into the Salton 
an “i well below sea-level. 
The delta is the home of the Cucopa Indians who build their 
es of arrow-weed (Pluchea sericea) and carry on their scant 
panee with respect to the periodic overflow. This winter 
flood, however, which had not occurred since 1891 and which 
recurs at intervals of about fifteen to twenty years, had seriously 
disturbed the movements of the entire tribe, the members of which 
which were now gathered in Poso Vicente and two or three 
small rancherias on the western margin of the delta, and a few on 
the eastern bank of the river above Colonia Lerdo. While the 
arrow-weed is as important and as useful for as many different 
purposes as the palm to the Pacific islander, yet the native here 
