_July 15th._—A long botanizing excursion to-day among the Tijuca hills with Mr. Glaziou, director of the Passeio Publico, as guide. It has been a piece of the good fortune attending Mr. Agassiz thus far on this expedition to find in Mr. Glaziou a botanist whose practical familiarity with tropical plants is as thorough as his theoretical knowledge. He has undertaken to enrich our scientific stores with a large collection of such palms and other trees as illustrate the relation between the present tropical vegetation and the ancient geological forests. Such a collection will be invaluable as a basis for palæontological studies at the Museum of Comparative Zoölogy in Cambridge. _July 23d._—At last our plans for the Amazons seem definitely settled. We sail the day after to-morrow by the Cruzeiro do Sul. The conduct of the government toward the expedition is very generous; free passages are granted to the whole party, and yesterday Mr. Agassiz received an official document enjoining all persons connected with the administration to give him every facility for his scientific objects. We have another piece of good fortune in the addition to our party of Major Coutinho, a member of the government corps of engineers, who has been engaged for several years in explorations on the Amazonian rivers. Happily for us, he returned to Rio a few weeks ago, and a chance meeting at the palace, where he had gone to report the results of the journey just completed, and Mr. Agassiz to discuss the plans for that about to begin, brought them together. This young officer’s investigations had made his name familiar to Mr. Agassiz, and when the Emperor asked the latter how he could best assist him, he answered that there was nothing he so much desired or which would so materially aid him as the companionship of Major Coutinho. The Emperor cordially consented, Major Coutinho signified his readiness, and the matter was concluded. Since then there have been frequent conferences between Mr. Agassiz and his new colleague, intent study of maps and endless talk about the most desirable mode of laying out and dividing the work. He feels that Major Coutinho’s familiarity with the scenes to which we are going will lighten his task of half its difficulties, while his, scientific zeal will make him a most sympathetic companion.[42] We found to-day some large leaves of the Terminalia Catappa of the most brilliant colors; red and gold as bright as any of our autumnal leaves. This would seem to confirm the opinion that the turning of the foliage with us is not an effect of frost, but simply the ripening of the leaf; since here, where there is no frost, the same phenomenon takes place as in our northern latitudes.