produced many other smaller kinds of sharks, often in near-perfect 

 condition of preservation, as well as large numbers of very fine speci- 

 mens of palaeoniscoid fishes. 



Many fossil vertebrates have to be described on the basis of a 

 single, often inadequately preserved specimen. As a consequence, 

 the systematic position of such animals is in continuous debate until 

 additional specimens are found. Dr. Robert Sloan, of the Depart- 

 ment of Geology of the University of Minnesota, recently recovered 

 and assembled from various places, including taverns, pieces of a 

 Cretaceous sediment containing the bones of an originally articulated 

 skeleton of a sea turtle. The rock is part of the waste material 

 stripped off the surface (of what once were granite islands in a late 

 Cretaceous sea) by commercial granite-quarrying companies in west- 

 ern Minnesota and extreme eastern South Dakota. Happily, most 

 of the skeleton was recovered and the pieces fit together perfectly. 

 Moreover, the remains could be identified as belonging to Desmato- 

 chdys lowi Williston, a rare sea-turtle known only from the rather 

 incompletely preserved type-specimen that was described by Willis- 

 ton more than sixty years ago and has puzzled students of fossil 

 turtles ever since. Dr. Sloan has offered this fine specimen to the 

 Museum in exchange for study materials. 



The most noteworthy additions to the fossil-mammal collection 

 were those made by the Museum's expedition to the Washakie Basin 

 (see page 53). Earlier expeditions to this basin have, with but few 

 exceptions, recovered the larger elements such as uintatheres, titano- 

 theres, rhinos, and smaller artiodactyls and horses. Curator Turn- 

 bull and Chief Preparator Gilpin, however, were lucky enough to 

 discover a microfauna that notably enhances the significance of this 

 important and valuable collection. 



Care of the Collections— Geology 



A complete inventory of the Museum's mineral collection was made 

 and those minerals that are not in the collection were listed. It was 

 found that the several thousand specimens in the collection represent 

 43 per cent of the known kinds of minerals. The collection of fossil 

 plants is being completely overhauled. In addition to the standard 

 records, an illustrated descriptive catalogue is being made for this 

 collection. In addition to routine repair of specimens accidentally 

 damaged while being studied, a fairly large number of specimens of 

 mammals, reptiles, and fishes was prepared and integrated into the 

 collection in spite of the fact that much of the time of the prepara- 



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