plant, which slowly absorbs their life-juices. How this plant, usually such a lover of watery places, manages to subsist on these rocks is mysterious.

Each evening, at dusk, the flocks of swifts (Acanthyllis collaris) spoken of by Mr. Brown arrived; but they were by no means as numerous as they seem to have been at the time of his visits. They fly high in the air above the fall, then so suddenly descend straight down into the amphitheatre, that their wings make a hissing noise which is not the least curious phenomenon of this wonderful place. After descending straight down, they settled for the night on the face of the cliff, by and behind the fall.

Here, too, we were lucky enough to obtain specimens of a new species of bird, which Mr. P. L. Sclater has done me the honour to name after me, Agelæus imthurni.

The nights were bitterly cold. The moon was big at the time, and as it shone on the fall seemed to make it grow more weird. The thunderous roar of its water sounded much louder than by day. Towards morning it became evident that masses of thick white clouds filled the whole valley below the fall; nor did these clear away till nine o'clock in the morning.

It was with regret that we turned, at last, to leave the Kaieteur, but after a six days' stay in the neighbourhood, it was time to start homeward.

No new or striking incident occurred during our return, and I may therefore bring my story to a close.

In the following February, at the end of a heavy rainy season, having a month's leave of absence, it seemed that the time could hardly be better employed than in again ascending the Potaro and seeing the fall of the river in flood. Mr. T. C. Edwards-Moss went with me; and with twenty Indians we started from Bartica Grove, in three boats, on Monday, the 10th of February, and, in spite of the large quantity of water both in the Essequibo and Potaro rivers, accomplished our journey comfortably, and so quickly that we were back