outcasts, are exclusive, and proud of their isolation. [Illustration: PUSHING THE DONKEYS INTO THE WATER PREPARATORY TO THEIR BEING FERRIED ACROSS. _See p._ 141.] On the morning of January 31 my companions took the Berthon boat and a whole cargo of surveyors’ gear, and started to complete the work for which the expedition had been organized. A full account of the results will be found in Sir William Garstin’s official Report on the Sources of the Nile. My services were not requested, and I certainly have had more practice in surveying symptoms than ground. I stayed in camp for awhile, and then walked to the river with angling-tackle, and landed a fair-sized fish with a spoon-bait. It was of the perch family. The country around Bahardar Georgis is flat, as I have said, and in places swampy. The marshy tracts are overgrown by papyrus, and it is not easy to distinguish them before one is both on and in them. On this moist ground we saw flocks of wild geese and various species of ibis. In the neighbourhood of the village I first observed the bird known as _buphaga Africana_. It pitched upon the backs of any of our donkeys that had sores, and caught the flies that settled there. The bodies of these birds are gray, and scarcely distinguishable from the donkey’s hide. Their beaks are red, and, at a little distance, I noticed that they exactly resembled a sore on the beasts which they infested. This colouring seems a remarkable example of evolution in the direction of “protective mimicry.” They worry cattle also, and it is well known that they peck the animals to make raw places, which then attract the flies that are caught upon them. I believe that they also use their beaks to mimic sores, for my attention was first drawn to the birds by the semblance of abrasions on the spinal area of some of the donkeys, where I knew that none existed. No doubt the beaks, used thus, are a successful trap. During the day I received a visit from an Abyssinian artist who lived at Bahardar Georgis. He came to beg colours from us, if we had any; I have no notion how the Habashes compound their pigments. He told me that he had a commission to execute some paintings for the church. I could only give him some pieces of red and blue pencil. He was extremely grateful for these, and bestowed upon me some samples of his art. I presented him to Dupuis, who was greatly interested by his pictures, and kindly took the trouble to discover, after much rummaging, an old box of paints. This he gave to the youth, whose delight was indescribable. He promised Dupuis works of art in his best style. In the evening he came to our camp again, and I showed him the Christmas Number of _Pearson’s Magazine_. This pleased him highly, especially when he found that he was to be the possessor of it. The three coloured plates caused him an ecstasy of wonder and pleasure, and the respective artists—and the colour-printers—have a venerating admirer by the lake-side.