Annotation in this volume again makes use of United States Geological Survey (USGS) maps and other maps not specifically cited in the sources. We continued to use Robert N. Bergantino's set of USGS maps (1° x 2°, 1:250,000) on which he has plotted Lewis and Clark's route, camps, and points of astronomical observation through Montana and part of Idaho (from Lemhi Pass to Lost Trail Pass). Bergantino was also kind enough to read the portion of this volume dealing with Montana. We used his maps in checking Lewis and Clark's locale and for obtaining modern place names but did not cite them in notes. For more detail we also used other USGS maps (30° x 60°, 1:100,000); these are cited in notes where used and are also listed in "Sources Cited."

Other special maps were also used but not cited in the sources. For the Bitterroot Mountains portion of the expedition we turned to the Salmon National Forest map (Lemhi Pass to Lost Trail Pass), the Bitterroot National Forest map (North Fork, Idaho, to Missoula, Montana), and the Clearwater National Forest map (Lolo Trail). Beyond the Lolo Trail, as the party entered modern Washington and Oregon, we returned to the USGS maps. As the notes indicate, we used extensively the works of Ralph Space and John J. Peebles about the Lolo Trail. Space was also generous enough to read the portion of the volume dealing with the trail and to provide us with useful comments. We have cited the articles Peebles published in Idaho Yesterdays in the 1960s. Not specifically cited but carefully consulted was his map of the Lolo Trail, which was published with his article about the crossing. The Idaho Historical Society later published Pebble's three articles (the third being about the expedition's return trip on the Lolo Trail) together as Lewis and Clark in Idaho , Idaho Historical Series Number 16 (December 1966). With these essays and map, Space's magnificent book, and the Clearwater National Forest map, one is fully prepared to follow the Corps of Discovery along the Lolo Trail.

Persons who have shown us kindnesses and courtesies in numerous ways deserve our gratitude for their help in carrying this project forward and they have our heartfelt thanks as friends and colleagues. John L. Allen, Donald Jackson, James P. Ronda, and W. Raymond Wood not only wrote books and essays which serve this endeavor well but also added personal encouragement and professional assistance in many ways. Robert E. Lange of Portland, Oregon, has done leg work for the project at the Oregon Historical Society and answered questions about the Columbia River portion of Lewis and Clark's trip, while Bob Saindon of Helena, Montana, has happily responded to some difficult questions about Montana nomenclature. Michael E. Dotson of Crest Hill, Illinois, reminded us not to overlook clothing as a Lewis and Clark topic. Advice for tracing the Lewis and Clark trail in their locales or places of interest came from Duane Annis (Orofino, Idaho), Stephen D. Beckham (Portland, Oregon), Fred Crandall (Nevada City, California), Ralph H. Rudeen (Olympia, Washington), and James R. Wolf (Bethesda, Maryland).

At the two principal repositories of Lewis and Clark expedition materials we have had the gracious assistance of able curators, librarians, and administrators: Beth Carroll-Horrocks, Edward C. Carter II, Roy E. Goodman, Randolph S. Klein, and Murphy D. Smith (all of the American Philosophical Society, Philadelphia); and Duane R. Sneddeker (Missouri Historical Society, St. Louis). At the project's office we have benefited from the work of a dedicated staff and research assistants: Jennifer Frost, Virginia J. Maca, Vernon Volpe, and Thomas Wakeley. Persons from the Center for Great Plains Studies, University of Nebraska–Lincoln, provided much-appreciated administrative help: Rosalind Carr, Georgia Lowenberg, Frederick C. Luebke, and Mary Lee Yetter. The Lewis and Clark Trail Heritage Foundation has continued to support the project financially as have individual contributors, Robert B. Betts (New York City), Gladys Levis (Alton, Illinois), William P. Sherman (Portland, Oregon), and Lyle S. Woodcock (St. Louis, Missouri). Their gifts lifted our spirits as much as they filled our coffers.

Scholars have been generous in their help in explaining Lewis's and Clark's references to their areas of expertise. The depth of the scientific annotation in this and other volumes owes its existence to such unselfish labors.

ARCHAEOLOGY: Kenneth M. Ames, Portland State University: Warren Caldwell, Orofino, Idaho; R. Lee Lyman, University of Missouri–Columbia. BOTANY: A. T. Harrison, Sandy, Utah. GEOLOGY: Robert N. Bergantino, Montana Bureau of Mines and Geology, Butte. LINGUISTICS: American Indian linguistic data in the notes were collected by Raymond J. DeMallie, Indiana University, and were provided by the following individuals: Shoshone. Sven Liljeblad, University of Nevada, Reno. All forms are given in the Numic orthography used by Catherine S. Fowler and Sven Liljeblad, "Northern Paiute," in Handbook of North American Indians, vol. 11, Great Basin, edited by Warren L. D'Azevado (Washington, D.C.: Smithsonian Institution, 1986). Additional and corroborative Shoshone data were provided by Wick R. Miller, University of Utah, and David Shaul, Indiana University–Purdue University, Fort Wayne. Flathead. Sarah G. Thomason, University of Pittsburgh. Nez Perce/Shahaptian (Sahaptin). Haruo Aoki, University of California, Berkeley, and Bruce Rigsby, University of Queensland, Australia. For Nez Perce orthography, see Haruo Aoki, Nez Perce Grammar (Berkeley: University of California Press, 1970). Chinook/Chinookan. Michael Silverstein, with additional data from Robert Moore, both of the University of Chicago. For Chinookan orthography, see Michael Silverstein, "Chinookans of the Lower Columbia," in Handbook of North American Indians, vol. 7, Northwest Coast, edited by Wayne Suttles (Washington, D.C.: Smithsonian Institution, 1990). METEOROLOGY: Jay S. Hobgood, University of Nebraska–Lincoln; ZOOLOGY: Royce E. Ballenger, University of Nebraska–Lincoln (frogs); Thomas O. Holtzer, University of Nebraska–Lincoln (insects); Paul A. Johnsgard, University of Nebraska–Lincoln (birds); John D. Lynch, University of Nebraska–Lincoln (fish).

Custom prescribes and honesty dictates that we state that none of these persons is responsible for any errors that might appear in this edition.