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transfer is a distinct possibility knowing the Monument Creek situation (past private hatcheries and private sporting clubs). However, the fossil evidence proves that the species once was present in the upper Arkansas River system. I therefore consider the creek chub as a Pleistocene relict native to the Arkansas River drainage of Colorado. The contemporary range of N. dorsalis does not include the Arkansas River basin. This species is common in the Platte River drainage of Colo- rado and Nebraska but in Kansas it is found only in the extreme north- eastern part of the state. No parallel situation exists as in the pre- vious species. It is highly unlikely that it entered the Arkansas River in the past and dispersed to Colorado without other populations surviving in other suitable areas in the lower Arkansas River valley. With this sit- uation ruled out one can then look to the distribution of other species. Both the blacknose shiner ~. heterolepis and Topeka shiner ~. topeka show similar overall ranges, but they have localized occurrences in the Arkansas River drainage of Kansas (Lee et al. 1980). These species are suspected of gaining access to the Arkansas River from the north via one of several past connections with the upper Great Plains drainage of the Pleistocene (Metcalf 1966; Pflieger 1971). However, there is a problem in drawing in- ferences from these species to ~. dorsalis. Two subspecies of ~. dorsalis are recognized, one with scales on the nape occurring in the central and eastern parts of the species range and one without scales on the nape from the western part. The specimens of ~. dorsalis from Monument creek are referrable to the subspecies without scales on the nape. This is counter- intuitive, because if N. dorsalis gained access to the Arkansas River via - --.- one of these past connections, it should be the other subspecies. This fact supports a bait-bucket transfer from the range of the western sub- species. If this is true it lessens the interpretation presented for the creek chub. Nevertheless, the other evidence for the creek chub is more compelling than that for the shiner. At present, the presence of ~. dorsalis in the Arkansas River drainage remains problematical until fur- ther evidence, if any, surfaces. REFERENCES Beckman, W. C. 1952. Guide to the fishes of Colorado. University of Colorado Museum, Boulder, USA. Cope, E. D. and H. C. Yarrow. 1875. Report upon collections of fishes made in portions of Nevada, Utah, California, Colorado, New Mexico, and Arizona, 1871-1874. United States Geographic~l Surveygs, George M. Wheeler, in charge 5:635-703. Cross, F. B. 1967. Handbook of fishes of Kansas. Museum of Natural History, University of Kansas, Miscellaneous Publications 45:1-357. Cross, F. B. and J. T. Collins. Natural History, University 3:1-189. 1975. Fishes in Kansas. Museum of of Kansas, Public Education Series Number 10