which communicates with an extensive system of backwaters and lakes, lying between this part of the river and the Japurá, 250 miles further west. The inhabitants of the Solimoens give the name of Cupiyó to this little-known interior water-system. A Portuguese, whom I knew very well, once navigated it throughout its whole length. He described the country in glowing terms. The waters are clear; some of the lakes are of vast extent, and the land everywhere is level and luxuriantly wooded. It is a more complete solitude than the banks of the main river, for the whole region is peopled only by a few families of Murá savages. The inhabitants of Ega, who are employed in the summer season in salting pirarucú, sometimes make their fishing stations on the sandy shores of one or other of these lakes. The largest of them, whose opposite or northern shore is said to be scarcely visible from the south side, is called Lake Múra, and is very seldom visited.
A number of long, straggling islands occur in midriver beyond Cudajá. We passed the mouth of the Mamiyá, a black-water stream, on the 18th, and on the 19th arrived at the entrance to Lake Quarý. This is not, strictly speaking, a lake, but the expansion of the united beds of several affluents of the Solimoens, caused by the slowly-moving waters of the tributaries originally spreading out over the flat alluvial valley, into which they descend from the higher country of the early part of their course, instead of flowing directly into the full and swift current of the main river. Henceforward most of the branch rivers exhibit these lake-like expansions of their beds. The same phenomenon takes a
