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-11- The only algae present was Cladophorasp. Stream vegetation, on the whole, was very sparce in this section. ~~~`~ .,, ... ~. , ~`~ - °-~ .. ~~ "+~'' " "-'a ..fl wry js' ~ -A "'. A. -z~Yer,., of rJ .~,+ _: +~~ t~a+s ,~ - o-r- Station No. 2 Looking Upstream at the Little Colorado Bridge The actual sampling site was on a large riffle, an extension of the rocky area in the foreground of the Station No. 2 photo. The bottom was composed of rock from 3 to 6 inches in diameter, Deposits of silt were noticeably heavier than at Station No. 1. This deposit remained on the gravel most of the year. Diatoms collected at this station with the diatometer showed a predominance of Fragilaria sp., and Cymbella sp. The Gomphonema sp., and Navicula increased over the amount present at Station No. 1. Occasional Cocconeis placentula, Diatomella sp., and Gyrosigma sp. were found. Zooplankton concentrations dropped in numbers at this station as compared to Station No. 1, The average number of organisms was 0.9 per liter. The or- ganisms found were almost exclusively rotifers, with an occasional copepod found. Bottom fauna was also smaller in numbers than in Station No. 1. The bulk of the organisms taken were Ephemeroptera and Diptera. The Diptera count being somewhat higher at this station. The only apparent change in water chemistry, as noted in Table VI, page 30, was a general increase in the total dissolved solids over the amount pre- sent at Station No. 1. Coliform counts were also quite low at this station; of the three plate counts made in November, 1958, two colonies were counted in one of the plates, the other two showed no development. The area from Station No. 2 to No. 3 is very similar to that between Sta- tions No. 1 and No. 2. Sagebrush is the dominant plant on lands overlooking the river, and greasewood, sagebrush and rabbitbrush dominate the area adjacent to the river bed. The soil is highly alkaline and subject to erosion during