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Samples of the benthos were collected from varying depths in the littoral zone in 1964 and 1965. In 1964 the depths sampled ranged from 10 to 20 feet in the canyon area and from 15 to 35 feet in the open area. During the 1965 sampling period, sample depths ranged from 7 to 25 feet in the canyon area, 20 to 22 feet in the open area and 10 to 12 feet in the inflow area. In 1966, samples were collected from three depths: one to two feet, 10 feet and 25 feet. Gear restric- tions and limited returns made sampling at depths greater than 25 feet impractical. Samples of the benthos were processed through two box type screens of 1 /8 inch and 1/16 inch wire mesh. Organisms were then separated from the remaining course material by sugar flotation. Vials containing a 10 percent solution of formalin were used to store the organisms until they were later processed in the laboratory. Taxonomic identification was made within practical limits. The organisms were counted in the laboratory and their volume determined by water displacement. RESULTS The 1964 data are very limited. The data specifies only whether an organism was present or absent from the samples. The organisms that were found in the reservoir in 1964 were midge larvae (Chironomidae), mayflies (Ephemoroptera), caddisflies (Trichoptera) and snails (Mollusca). Chironomids were present in all of the samples taken in the canyon and open areas. Mayflies, caddis- flies and snails were present in 25 percent of the samples from each area (Table 1). One sample taken from a depth of 95 feet produced only Chironomids. The data collected in 1965 represent samples collected in July. Table 2 summarizes the limited information. Chironomids continued to be the most abundant organism in the samples. The 1966 data were more comprehensive because of the collection method used. In the open area, the productive habitat generally exceeded the unproductive habitat in number of organisms per square foot. The only exception was at the 25-foot depth in July (Figure 2). The number of organisms per square foot in the unproductive habitat was small as compared with the productive habitat throughout the sampling period in the open area. The May sampling produced the largest number of organisms with 16.7 per square foot at the 10-foot depth and 25.5 per square foot at the 25-foot depth (Table 3). In the inflow area, the number of organisms sampled in the produc- tive habitat also exceeded those sampled from the unproductive habitat 34