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OPERATIONS Camp was established at the foot of Rollins Peak, on the northeast shore of Lake itfinnemucca, Pershing County, Nevada, Excavations were car­rier out to completion in Crypt and horse Caves, Field reconnaissance by Miss Simpson was carried out along the lake terraces surrounding the lake, with the exception of the land on the south and east shores which lie with­in the Pyramid Lake Indian Reservation, for which no permit was had. Numerous low level sites were found dating less than 10,000 years, and two high level sites were found which may be presumed to be 10,000-12,000 years old. A contour map of Rollins Peak area of 20 foot intervals was completed by Charles Taylor. Orr completed the field studies and a preliminary aeri­al geology sheet of the same area, also a geoch.rcno,logical sheet which will show the lake levels at given periods in the past, from the present dry lake to 30,000 years BP. Briefly, this will show a high lake at 12,000 years, an intermediate lake at 20,000-14,000, an extremely low at 13,000, and a high at 10,000, after which the lake gradually retreated. This is based upon^th: geomorphic studies carried out by Orr, Broecker and Giletti, and radiocarbon dates by Kulp and Broecker. A special effort was made to collect materials which it is hoped will serve for geochronological measurements covering the time periods from whicl we have the least data, as prior to 20,000 years and less than 6 ,000. For the past three years, Dr. Paul B. Sears, Yale University, has been studying the pollen from the Winnemucca Caves. New samples were collected from this season's excavations which will be forwarded to Dr. Sears, and a complete botanical collection of plants were collected by Kerlan, and are being identified by Clifton Smith, Santa Barbara Liuseum of Natural History. Our excavations in Crypt Cave were carried to a cemented bottom of tufa and cobbles in which we passed through lake sediments radiocarbon dated at 20,000 years, and human occupational material dating to 11,000 years. The skull, jaws, and a portion of the skeleton of a large cat was found below the 20,000 year level. The nearly complete skeleton of a Farallone cormo­rant was found also, as were numerous shells, and bones of small birds and rodents. The history of the cave was graphically illustrated in this deep exca­vation in which the lake has occupied and abandoned the cave several times only to be occupied by man and animals since 10,000 years ago, This will be published at a later date (Orr, Kulp and Broecker). The archeological excavations produced quantities of basketry, cordage and wooden objects, covering a time span estimated at 9,000 years, which will take several years of study before a complete and final report can be given. At the present writing, July 1957, the following scientists are en­gaged in some phase of the study of our collections: Phil C. Orr, WSI-SBMNH., general director, paleontology, speleology, geomorphology and archeology Louise G, Reid, assistant to the director —2—