THE FISHES (OR THE: ROCKY MOUNTAIN 
REGION 
By T. D. A. COCKERELL 
For class use, and in connection with my studies of the Rocky Moun- 
tain fauna, I have found it necessary to prepare an abstract of our knowl- 
edge concerning the fishes of the Rocky Mountain region. The area 
covered is roughly Montana, Wyoming, Colorado and New Mexico, 
but the boundaries have been somewhat extended here and there to 
include certain species. The fossil species are given, although it is 
anticipated that fresh discoveries will greatly enlarge our knowledge 
of these in the near future. A good series which the University Expedi- 
tion of 1907 obtained in the Miocene shales of Florissant is now being 
studied by Dr. Eastman. 
The information given in this paper is compiled from the literature, 
with the exception of the results of a study of the fishes of Boulder 
County, based on material in the University of Colorado Museum, mostly 
collected by Mr. Chancey Juday. By far the greater part is derived from 
the monumental work of Jordan and Evermann on the Fishes of North 
and Middle America (Bull. 47, U. S. Nat. Museum), which is the main 
source of information for all students of American ichthyology.* American 
Food and Game Fishes, by the same authors, but of later date (1902), 
has also been found exceedingly useful. The basis of our knowledge 
of Boulder County fishes is the paper by Professor Chancey Juday in 
University of Colorado Studies, Vol. Il, p. 113, and Bull. U. S. Bureau 
of Fishes, March 17, 1905. In these papers, unfortunately, the diagnostic 
characters of the fishes (excepting the new Leuciscus) are not given; 
these I have endeavored to supply. For records of the fossil species, I 
am primarily indebted to the invaluable catalogue of the Fossil Vertebrata 
of North America, by O. P. Hay (Bull. 179, U. S. Geol. Survey, 1901). 
I am exceedingly indebted to Dr. B. W. Evermann, who has kindly 
t The figures illustrating the present paper are derived from this work, with the kind permission of the 
authorities of the National Museum. 
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