I was indebted to the President for many valuable specimens on this excursion, many of the birds and fishes brought in by the Indians for the table being turned over to the scientific collections. My young friends Dexter and James were also efficient, passing always a part of the day in the woods, and assisting me greatly in the preparation and preservation of the specimens. Among others we made a curious skeleton of a large black Doras, a species remarkable for the row of powerful scales extending along the side, each one provided with a sharp hook bent backward. It is the species I have described, in Spix and Martius’s great work, under the name of Doras Humboldti. The anterior vertebræ form a bony swelling of a spongeous texture, resembling drums, on each side of the backbone.—L. A. CHAPTER IX. MANAOS AND ITS NEIGHBORHOOD. PHOTOGRAPHIC ESTABLISHMENT.—INDIAN PORTRAITS.—EXCURSION TO THE “GREAT CASCADE.”—ITS GEOLOGICAL FORMATION.—BATHING POOL.—PARASITIC PLANTS.—RETURN BY THE IGARAPÉ.—PUBLIC BALL.—SEVERITY IN RECRUITING, AND ITS EFFECTS.—COLLECTING PARTIES.—SCENES OF INDIAN LIFE.—FÊTE CHAMPÊTRE AT THE “CASA DOS EDUCANDOS.”—PRISON AT MANAOS.—PRISON DISCIPLINE ON THE AMAZONS.—EXTRACTS FROM PRESIDENTIAL REPORTS ON THIS SUBJECT.—PRISON AT TEFFÉ.—GENERAL CHARACTER OF BRAZILIAN INSTITUTIONS.—EMPEROR’S BIRTHDAY.—ILLUMINATIONS AND PUBLIC FESTIVITIES.—RETURN OF COLLECTING PARTIES.—REMARKS ON THE RACES.—LEAVE MANAOS FOR MAUHES. _Saturday, November 4th._—Manaos. This week has been rather uneventful. Mr. Agassiz is prevented from undertaking new expeditions by the want of alcohol. The next steamer will bring a fresh supply from Pará; and meanwhile, being interrupted in his collections, he is making a study of the various intermixture of races, Indians and Negroes, with their crossings, of which a great number are found here. Our picturesque barrack of a room, which we have left for more comfortable quarters in Mr. Honorio’s house, serves as a photographic saloon, and here Mr. Agassiz is at work half the day with his young friend Mr. Hunnewell, who spent almost the whole time of our stay in Rio in learning photography, and has become quite expert in taking likenesses. The grand difficulty is found in the prejudices of the people themselves. There is a prevalent superstition among the Indians and Negroes that a portrait absorbs into itself something of the vitality of the sitter, and that any one is liable to die shortly after his picture is taken. This notion is so deeply rooted that it has been no easy matter to overcome it. However, of late the desire to see themselves in a picture is gradually gaining the ascendant, the example of a few courageous ones having emboldened the more timid, and models are much more easily obtained now than they were at first.