Henderson, Kenneth, _Handbook of American Mountaineering_. Houghton Mifflin Co., Boston, 1942. A pocket-size book, almost encyclopedic in scope, giving detailed information on mountain climbing and life on the trail. Nesbit, Paul, _Longs Peak, Its Story and a Climbing Guide_. Published by Paul W. Nesbit, Colorado Springs, Colo., 1959. Ormes, Robert M., _Guide to the Colorado Mountains_. Sage Books, Denver, 3d revised edition, 1955. _Parks in General_ Butcher, Devereux, _Exploring Our National Parks and Monuments_. Houghton Mifflin Co., Boston, 4th edition, 1954. In cloth or paper covers; illustrated; gives succinct information on all our parks with natural-history backgrounds. Shankland, Robert, _Steve Mather of the National Parks_. Alfred A. Knopf, New York, 1955. The evolution of the National Park System and the life of the first director of the National Park Service. Story, Isabelle, _National Park Story in Pictures_. Government Printing Office, Washington, D.C., 1957. Tilden, Freeman, _The National Parks: What They Mean to You and Me_. Alfred A. Knopf, New York, 1955. Factual material on the parks, their significance, origins, and characteristics. APPENDIX A—GUIDE TO MAMMAL OBSERVATION _Hoofed Mammals_ _Bighorn_ (mountain sheep)—Best seen on Sheep Rock south of Poudre Lake; also at Sheep Lake, Shipler and Specimen Mountains, Hallett’s Peak, Mount Alice, Never Summer Range, Mount Ida. _Deer, Mule_—Occasional in open pine country, especially early and late in the day. Hillside above Tuxedo Park, Moraine Park, Deer Mountain, Trail Ridge, and Kawuneeche Valley. _Elk, American_—At treeline on Trail Ridge, Upper Poudre Valley, and near Lawn Lake in summer; occasionally in Hallowell and Horseshoe Parks during bad weather. Large herds in lower meadows from October to April. _Predatory Mammals_ _Badger_—Occasional in Moraine Park and other open meadow areas. _Bear, black_—Uncommon; infrequently observed along roads and trails and in wooded areas throughout the park. _Bobcat_—Common, but in ravine country, especially at lower elevations. _Cougar_ (mountain lion)—Uncommon; occasionally seen above Loch Vale, Horseshoe Park, upper Fall River Valley; typical habitat around Gem Lake. _Coyote_—Common, especially in Hallowell Park, lower Cub Lake Valley, Moraine Park, lower Beaver Meadows; signs on Deer and Specimen Mountains. _Fox, red_—Fairly common at or above treeline, along the Colorado River, and in the Kawuneeche Valley. _Marten_—Occasional at Bear Lake, Haiyaha, Fern-Odessa Trail, Lulu City; usually in spruce-fir forest. _Mink_—Occasional along higher streams and lakes like Haiyaha.