_Falcon Creek_--R : 13--1885--U. S. G. S.--Characteristic. _Falls River_--S : 1--1872--U. S. G. S.--Characteristic. _Fan Creek_--C : 2--1885--U. S. G. S.--Characteristic. _Fawn Creek_--C : 5--1878--U. S. G. S.--Characteristic. _Firehole River_--I : 4--This name and "Burnt Hole" have been used to designate the geyser basins and the stream flowing through them since at least as far back as 1830. Captain Bonneville says it was well known to his men. The term "Hole" is a relic of the early days when the open valleys or parks among the mountains were called "holes." The descriptive "fire, naturally arose from the peculiar character of that region." _Firehole, Little_--L : 4--1878--U. S. G. S.--From main stream. _Flint Creek_--F : 13--1885--U. S. G. S.--Characteristic. _Forest Creek_--Q : 7--1885--U. S. G. S--Characteristic. _Fox Creek_--R : 11--1885--U. S. G. S.--Characteristic. _Gallatin River_--A : 1--1805--Lewis and Clark--For Albert Gallatin, Secretary of War under President Jefferson. _Gardiner River_ (5360)--B : 6--This name, which, after "Yellowstone," is the most familiar and important name in the Park, is the most difficult to account for. The first authentic use of the name occurs in 1870, in the writings of the Washburn party. In Mr. Langford's journal, kept during the expedition, is the following entry for August 25, 1870: "At nineteen miles from our morning camp we came to Gardiner River, at the mouth of which we camped." As the party did not originate the name, and as they make no special reference to it in any of their writings, it seems clear that it must already have been known to them at the time of their arrival at the stream. None of the surviving members has the least recollection concerning it. The stream had been known to prospectors during the preceding few years as Warm Spring Creek, and the many "old timers" consulted on the subject erroneously think that the present name was given by the Washburn Party or by the Hayden Party of 1871. What is its real origin is therefore a good deal of a mystery.