While rambling up some of the narrow and rocky defiles, I could almost have fancied myself transported back again to the barren valleys of the island of St.
Jago.

Among the basaltic cliffs I found some plants which I had seen nowhere else, but others I recognised as being wanderers from Tierra del Fuego.

These porous rocks serve as a reservoir for the scanty rain-water; and consequently on the line where the igneous and sedimentary formations unite, some small springs (most rare occurrences in Patagonia) burst forth; and they could be distinguished at a distance by the circumscribed patches of bright green herbage.
(PLATE 42.

BASALTIC GLEN, SANTA CRUZ (RIO NEGRO).
APRIL 27, 1834.
The bed of the river became rather narrower, and hence the stream more rapid.

It here ran at the rate of six knots an hour.