Regarding the interesting question of the origin of Lake Nyassa and its great sister-lakes in the heart of Africa--the Victoria and Albert Nyanza and Tanganyika--I do not presume to speak. No follower of Ramsay in his theory of the glacial origin of lakes could desire a more perfect example of a rock-basin than that of Lake Nyassa. It is a gigantic trough of granite and gneiss, three hundred miles in length, nowhere over fifty miles in breadth, and sixteen hundred feet above the level of the sea, the mountains rising all around it, and sometimes almost sheer above it, to a farther height of one, two, and three thousand feet. The high Tanganyika plateau borders it on the northern shore, and the greatest depth is precisely where the glacial theory would demand, namely, towards the upper portion of the lake. On the other hand, the physical geology of the country in which these other lakes are situated, as well as several features connected with Lake Nyassa itself, lend no countenance to such a view; and probably the suggestion of Murchison and other geologists is correct, that all these lakes, colossal though they still are, are the remnants of a much vaster expanse of water which once stretched over Central Africa. The only other point to which I need allude is the subject of glaciation itself. And I refer to this pointedly, because I have lately encountered allusions, and in quarters entitling them to respect, to the presence of glacial phenomena in the Central Lake district of Africa. I confess that my observations have failed to confirm these suggestions. It has been my lot to have had perhaps exceptional opportunities of studying the phenomena of glaciation in Europe and Northern America, and I have been unable to detect anywhere in the interior of Africa a solitary indication of glacial action. In Kaffirland, far to the south, there are features which one would almost unhesitatingly refer to glaciation; but in East Central Africa not a vestige of boulder-clay, nor moraine matter, nor striæ, nor glaciated surface, nor outline, is anywhere traceable. One would be curious to know to what extent the flora and fauna of the inland plateau confirm or contradict this negative evidence against the glaciation of this region.