The afternoon was devoted to an examination of the heights on the north-east side of the Yana-mayu, where, at an elevation of 450 feet, there is a level table-land, covered with palms and bamboos. The search was chiefly conducted along a ridge above this plateau, where the bamboos ended. We obtained twenty more plants of _C. Calisaya_, one of which was declared by Martinez to be a _Calisaya morada_ (_C. Boliviana_, Wedd.), and the leaf agreed well with Dr. Weddell's description, though that botanist believed that the species was not found in this part of Caravaya, but only in the valleys of Ayapata, further north. To-day we saw a couple of _tunquis_,[335] birds with the most gorgeous plumage I ever beheld. They are the size of large pigeons, with orange-scarlet feathers on the head, neck, breast, and tail, black wings, light-grey back, and scarlet crest. They have a shrill, harsh cry. The butterflies and moths were numerous and brilliant, but so tame, and in such swarms, as to be a perfect plague. There was one bright swallow-tail, with blue wings, fringed with crimson. The torments from venomous insects were maddening; especially from a kind of fly which in a moment raised swellings and blood-red lumps all over the hands and face, causing great pain and irritation. During the night it rained heavily, with peals of thunder, and vivid flashes of lightning, while the river increased in size, and roared past the tent noisily. The collection of chinchona-plants was deposited in a shady place, near the tent, the roots being well covered over with soft moss. On the morning of May 4th the river was so swollen as to destroy all hopes of crossing it for the present. It frequently changed its colour, on one morning the surging flood being black, on another tolerably clear, and on another a light muddy colour. By these means Martinez could always tell where the rains had been heaviest, and what stream was contributing an unusual freshet to swell the waters of the Tambopata.