SECRETARY'S REPORT 71 



From July 1 to September 25, 1951, six key sites were excavated in 

 the Keyhole Reservoir on the Belle Fourche River in Crook County, 

 Wyo. The excavated sites include one large protohistoric camp with 

 pottery remains, three prehistoric camp sites, and two stratified rock 

 shelters. The lowest levels in both rock shelters are manifestations 

 of a new early-man complex. The data indicate that the aboriginal 

 occupation of the Keyhole area may have started about 5,000 years ago. 

 Much more recent materials were found in the upper levels and in a 

 few cases there were potsherds from vessels of the so-called Woodland 

 types. The latter are significant because they extend considerably 

 westward the known range of that kind of Indian pottery. The in- 

 vestigations at the Keyhole Reservoir have been completed. 



The Jamestown Reservoir on the river of the same name in North 

 Dakota was listed for investigation for the first time since the start 

 of the program. A survey party was supposed to make a reconnais- 

 sance there in the fall of 1951 but because of bad weather was unable 

 to do so. As a consequence a combined survey and excavating party 

 went there in May 1952. After 3 weeks' preliminary examination of 

 the area and 18 sites had been located, excavations were started in a 

 mound 75 feet in diameter and 10 feet in height located on a bluff, 

 and in some house remains on the bottom lands. The mounds in that 

 portion of North Dakota show considerable similarity to those in 

 northern Minnesota and southern Manitoba and all probably belong 

 to the same cultural complex. The actual people involved have not 

 been identified as yet, and as little is known about the character of 

 the remains the results of the investigations there should add mate- 

 rially to knowledge about the Indians. The work there had not 

 progressed sufficiently by June 30 to permit a statement about the 

 findings. 



During the 1951 field season the paleontological party visited and 

 collected in five reservoir areas, two in Montana, one in North Dakota, 

 and two in South Dakota. In exploring the Oligocene and Miocene 

 deposits in the Canyon Ferry Reservoir basin in Montana the party 

 added two genera of small mammals to the known fauna of the Oligo- 

 cene and six genera of those of the Miocene. While the sediments of 

 the Montana group of the the Upper Cretaceous were being studied 

 near the dam for the Oahe Reservoir, S. Dak., the first nearly complete 

 skeleton of one of the pygmy species of mosasaur, genus Clidastes, 

 ever obtained was found. The 1952 field season's work started with 

 a preliminary reconnaissance of the Tuttle Creek and Lovewell Reser- 

 voir basins in the Kansas River drainage, Kansas, and was followed 

 by surveys of three reservoir areas in the Platte Drainage. They 

 were the Narrows in Colorado, and the Ashton and Trenton in 

 • Nebraska. Preliminary prospecting was also carried on at the Gavins 



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