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RESULTS Nine fish identified as possible G. elegans were captured during a 7- day trip through Cataract Canyon on July 12-18, 1988 (Table 1). Three of these fish were classified as adults; 383, 365, and 306 nun TL. The remaining six fish were considered to be juveniles and ranged in size from 235 to 294 nun TL. Photographs of the four largest fish are presented in the enclosed sheets along with detailed meristics. Also presented for comparison are photographs and meristics of three of the G. elegans that were transferred from the Dexter National Fish Hatchery for radioimplant and release at Island Park and Split Mountain of the Green River on July 28, 1988. The complete set of meristics were recorded for all nine fish from Cataract Canyon (CA07/15) as well as ten fish transferred from Dexter (DX07/28). Five additional G. elegans from Dexter but held at OUray were briefly examined. DlsaJSSICN Close examination of the photographs and meristics for the Cataract fish and the Dexter fish reveal subtle differences between the two groups. Examination of the photographs on sheets 1 (Cataract fish) and 2 (Dexter fish) show basic differences in body shape, particularly in the anterior regions. The most noticeable difference is that the Dexter fish exhibit a smooth nape with a markedly concave frontal depression and a small head; in contrast, the Cataract fish possess a more abrupt hump-like nape and a smoothly concave frontal with a more robust head. Aside from differences in coloration and apparently coarser scales on the Dexter fish, the two groups have similar body shapes, including a narrow, elongated caudal peduncle and caudal fins. A photograph of the tubercled head of Dexter fish no. 4146 is also presented to show the pre-spawning condition of the males, a condition that has only been seen in humpback chubs in Cataract Canyon. The greatest meristic difference between the two groups of fish is that all of the Dexter fish possess 10 dorsal and 10 or 11 anal rays; only two Cataract fish possess these ray counts and the rest had 9 dorsal and 10 anal rays. As for the ratio of caudal peduncle length to head length, all ten Dexter fish exhibited CPLjHL ratios greater than 1.00; six of the nine Cataract fish exceeded CPLjHL ratios of 1.00. The ratio of head length to caudal peduncle minimum depth did not exceed 5.00 for any fish of either group. Based on this brief examination of photographs and meristics, it appears that the fish from Cataract Canyon possess at least some genetic influence of G. elegans. The strongest impression of this influence comes from handling these fish afield; from a general examination of body shape, scale distribution and coarseness, head shape, etc. Unfortunately, photographs tend to compress the three-dimensional aspect of a fish so that they often appear somewhat different in photos than what memory seems to recall. I hope the similar photographs of the OUray fish will tend to 'neutralize' this effect.