Department of Geology 



Research and Expeditions 



Dr. Sharat K. Roy, Chief Curator of Geology, aided by a grant from 

 the National Science Foundation, left the Museum in mid September 

 on a study trip to Western Europe, where he is currently engaged in 

 research on meteorites. Before leaving he finished two studies on 

 Central American volcanoes and a third on the structure of chon- 

 drules in stony meteorites (see page 91). Earlier in the year he spent 

 three months in the field continuing his studies of the volcanoes of 

 Mexico and Central America with particular emphasis on those of the 

 central range of Costa Rica (see page 34). 



Albert William Forslev, Associate Curator of Mineralogy and 

 Petrology, has begun a study of the mineralogy and crystal chemical 

 relationships of niobium-bearing minerals following the installation 

 of the William J. and Joan A. Chalmers Mineralogical Laboratory 

 that houses an X-ray diffraction and X-ray fluorescence unit. This 

 new equipment was subjected to extensive initial testing and has 

 since been used for the identification and analysis of many rock and 

 mineral specimens. 



Collecting specimens of fossil plants by George Langford, Curator 

 of Fossil Plants, has been restricted to several one-day trips. Cura- 

 tor Langford has continued to work with the large collection of Penn- 

 sylvanian plant materials from the strip-mine area of Will and 

 Grundy counties, Illinois, and has identified a large number of speci- 

 mens brought to the Museum by amateur collectors. He has con- 

 tinued to work on his nontechnical catalogue of the unusually varied 

 flora of the Mazon Creek nodules. 



In the various divisions of paleozoology William D. Tumbull, 

 Assistant Curator of Fossil Mammals, submitted for publication a 

 study of a Late Cretaceous marsupial mammal from the Lance for- 

 mation of Wyoming as well as notes on a mastodon of late Wisconsin 

 age from Indiana and on the tjrpe specimen of a species of Phlegethon- 

 tia, a Pennsylvanian limbless tetrapod. Besides making a compara- 

 tive anatomical and functional investigation of the jaw mechanism 

 of mammals, he carried on studies pertaining to the mammalian 

 fauna of the Washakie formation of Wyoming that was deposited 

 forty-five or fifty million years ago in mid-to-late Eocene time. The 

 mammalian faunas of that time consist of an interesting mixture of 

 terminal members of archaic mammal groups, quite unlike those 

 familiar to us today, that dominated the scene during an earlier 



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