82 REPORT OF NATIONAL MUSEUM, 1924 



Mr. Boss made several short collecting trips to the Miocene de- 

 posits along Chesapeake Bay and, as in previous years, was success- 

 ful in recovering well-preserved cetacean remains. 



Assistant Curators Shannon and Foshag, on their own initiative, 

 made several brief trips to near-by localities where small representa- 

 tive collections of rocks, minerals, and ores were secured. Early in 

 June, 1924, Doctor Foshag joined a field party of the United States 

 Geological Survey in Nevada, where he spent the summer. The 

 head curator spent some days inspecting quarries at Deer Isle and 

 Auburn, Me., and in a geological trip into the northern part of the 

 State. He represented the University of Maine at the inauguration 

 of the president of St. John's College at Annapolis, and the Smith- 

 sonian Institution at the inauguration of presidents of Washington 

 University at St. Louis and University of Missouri at Columbia. He 

 also represented the Institution at the centenary of the birth of 

 Joseph Leidy, at Philadelphia. 



Preservation, installation, and present condition of the collec- 

 tions. — Few changes have been made in the exhibition series. Prob- 

 ably the most striking additions within the year are those in the 

 hall of vertebrate paleontologj^. Here has been mounted the Pliocene 

 mastodon from Arizona which has been described by Dr. J. W. 

 Gidley under the name Stegomastodon arizonae. This is the only 

 articulated skeleton of this genus in America. Thomas Home, 

 preparator in the division, spent many months in the restoration 

 and mounting of this skeleton and is to be highly commended on 

 the successful outcome of his work. A large slab of rhinoceros bones 

 from Agate, Nebr., the preparation of which required months of 

 tedious work on the part of Norman H. Boss, and an interesting slab 

 from the Triassic of Virginia, showing footprints of a dinosaur, 

 were also installed, while further additions are a bison skeleton from 

 Minnesota and a cast of a skull of the fossil rhinoceros BalucM- 

 therium. 



In the adjoining paleobotanical hall, a fossil tree stump from the 

 Devonian of New York, found during excavations for Gilboa dam, 

 forms an important addition to the exhibits. Smaller mounts of 

 fossil plants have been added to the stratigraphic and biologic series, 

 and several cases have been bettered by rearrangement. 



An instructive addition in the hall devoted to systematic and physi- 

 cal geology is a series of large photographs, 20 in number, hung 

 above the exhibits which they admirably supplement. 



Two new cases, one containing Canadian silver-nickel ores and the 

 other rocks and associations from the Arkansas diamond fields, are 

 the chief additions to the series in economic geology, although a few 

 exceptionally fine specimens were added to the other case exhibits, 



