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Valdez and Clemmer (1982) and Valdez et al. (1982) above, with the majority of chubs collected up to that time clearly identifiable to species. States that G. robusta appears to -'? be a "distinct species" in all reaches except where syntopic with G. c ha. No elegans or suspected hybrids or "variants" thereof were found in the study. Discusses the application of meristic and mensural characters as given in Smith et al. (1979) to distinguish between cypha and robusta and states that this criteria separated specimens from Cataract, Black Rocks, and Westwater canyons but Debeque Canyon specimens were problematic. Based on later studies, - some percentage of material from the other canyon areas mentioned proved problematic as well. 1985c. Valdez, R.A. A review of the hatchery program for threatened and endangered fishes of the Colorado River. Ecosyst. Res. Inst. Rpt. to Colo. Water Congr. 31 p. Although primarily a review of the program to culture endangered species, including chubs, this report documents inportant information about brood stock used in the culture of G. cvpha and G. elegans and the distribution of their offspring. of particular interest is the fact that the brood stock of G. cvpha may have been derived from both Little Colorado River stock (lower basin) and upper Colorado River stock, thus mixing these genepools. Progeny from this operation were stocked in the Cataract Canyon area in 1981, thus possibly contaminating whatever natural gene pool might have been in place there and possibly clouding the results of any interregional studies of genetic variation in the humpback chub which might be undertaken. Preserved offspring could also conceivably be involved in taxonomic studies. Concerning bonytails, except for a few radio telemetry specimens released in the upper basin, that portion of the progeny of these chubs to be released were returned to the brood stock locality, Lake Mohave, Arizona. 1985. Woodling, J. Colorado's little fish: a guide to the minnows and other lesser known fishes in the State of Colorado. Col. Div. Wildlf., Denver. 77 p. An identification manuel to Colorado fishes which includes keys, good descriptions, and good photographs of Colorado River Gila spp. Presents a sketchy discussion of taxonomic history of the group and relates the problem of supposed bybridization in disturbed habitats. 1986. Demarais, B.D. Morphological variation in Gila (Pisces: Cyprinidae) and geologic history: lower Colorado River basin. Unpub. Ms. Thesis, Ariz. St. Univ., Tempe. (Not seen). Presumably reexamines populations earlier examined by Rinne (1976), and perhaps additional populations, 18