REPORT OP NATIONAL MUSEUM, 1018. 57 



Before leaving the division Dr. Edgar T. Wherry prepared a 

 paper entitled " Notes on mimetite, thaumasite, and wavellite," which 

 is in press, and he has since made constant use of the collections. 

 Prof. Glenn V. Brown, of Bucknell University, Lewisburg, Penn- 

 sylvania, utilized the collections and the chemical laboratory for 

 some weeks. 



The resources of the department were also of service to scientific 

 investigators engaged in war work, materials having been forwarded 

 to the Bureau of Standards, Geophysical Laboratory, Astrophysical 

 Observatory, National Research Council, Frankford Arsenal, and 

 American University Experimental Station. Mr. G. F. Loughlin, 

 of the United States Geological Survey, examined all vesicular rocks 

 in the collection to determine availability for use in the construction 

 of concrete ships, and to list localities where such material could be 

 obtained economically. 



Invertebrate paleontology. — A collection comprising 9,679 speci- 

 mens of Middle Cambrian fossils, obtained by Secretary Walcott 

 from the celebrated locality at Burgess Pass, British Columbia, was 

 deposited by the Smithsonian Institution. These form study and re- 

 serve material of this wonderful fauna, the types having been de- 

 posited previously. 



In addition to the exhibition and study material heretofore men- 

 tioned, Dr. R. S. Bassler collected a number of large fossils, mainly 

 corals, and fossiliferous limestone slabs for the purpose of enlarg- 

 ing the coral reef installed in the exhibition series last year. 



Over 500 specimens of well-preserved invertebrate fossils from the 

 Cretaceous formation of Tennessee, purchased during the year, 

 formed the most important addition to the Mesozoic collections. A 

 second purchase, acquired from Prof. D. S. Martin, Brooklyn, New 

 York, consisted of 110 specimens of fossil insects preserved in copal 

 resin, of interest for both exhibition and study. These were the re- 

 sult of many years of collecting on the part of Prof. Martin, who 

 obtained them by searching through the gum copal from the Pleisto- 

 cene deposits of East Africa, shipped in large quantities to the 

 varnish factories in the vicinity of Brooklyn. 



Various exchanges added valuable material to both the exhibition 

 and study series. Two lots were received from Mr. W. E. Crane, 

 Washington City, the more important being 1,500 specimens repre- 

 senting 500 species of Paleozoic and Mesozoic fossils, especially se- 

 lected to round out the study series of European forms, the second 

 lot containing 400 ammonites from the Jurassic rocks of France, 

 needed in the revision of the exhibit of these forms. Two lots from 

 Dr. F. C. Clark, Los Angeles, California, added to the study series 

 approximately 1,200 specimens of Tertiary fossils from the Pacific 



