Papers descriptive of the _botanical_ collection, prepared by Mr. Elias Durand; of the _algæ_, by Mr. Ashmead; of the _lichens_, by Professor James; of the _birds_, by Mr. John Cassin; of the _invertebrata_, by Dr. William Stimpson; of the _mammalia_, by Dr. J. H. Slack; of the _cetacea_, by Professor E. Cope; of the _infusoria_, by Dr. F. W. Lewis; of the _fishes_, by Dr. Theodore Gill; and of the _paleontology_, by Professor F. B. Meek, have appeared from time to time in the "Proceedings of the Academy of Natural Sciences of Philadelphia," excepting the last, which was published in the American "Journal of Arts and Sciences." Dr. J. Atkin Meigs has in preparation a monograph on _ethnology_, based upon a collection of upward of one hundred and forty specimens, and I shall soon have completed a more elaborate discussion of the Greenland Glaciers and other collateral topics than has been allowed me by the limits and character of this work. I should do great injustice to my own feelings, did I not here express the acknowledgment of my obligation to those societies, associations, and individuals who united themselves with me in effecting the organization of the Expedition, and who liberally shared with me its expenses. My wishes were always promptly met by them, to the extent of their ability; and the enterprise was sustained with a zeal and interest rarely accorded to a purely scientific purpose. That I have not before published an account of my voyage, or presented any detailed statement of my discoveries to those who had a natural right to expect it, has been entirely owing to the circumstance that my time has been wholly occupied in the public service, from the period of my return until late last year; and they will, I trust, accept as a sufficient excuse for my silence during that period, the fact that the command of an army hospital, with from three to five thousand inmates, which devolved upon me during the greater part of the recent war, allowed me little leisure for literary or scientific work. It will also be understood that the temporary abandonment of the exploration was due to the same general cause. _October 23d, 1866._ LIST OF SUBSCRIBERS TO THE EXPEDITION.[1] [Footnote 1: The author has reason to suppose that there are several persons to whom the Expedition is indebted for support whose names, not having been furnished him, do not appear in this list. Desiring to make it entirely complete, he will feel personally obliged to any one whose name is omitted to notify him of the fact, through the agency by which the subscription was furnished.] [Illustration] THROUGH A SPECIAL COMMITTEE OF THE AMERICAN GEOGRAPHICAL AND STATISTICAL SOCIETY, NEW YORK. EGBERT L. VIELE, _Chairman_; HENRY GRINNELL, _Treasurer_.