108 EEPORT OF NATIONAL MUSEUM, 1&20. 



"without a head. The most pressing woi'k, therefore, Avas to relieve 

 the congestion in the recorder's office. This involved the unpacking 

 of a large collection transferred from the U. S. Naval Academy 

 some months before, "which, "while of a ver}- miscellaneous nature, 

 yielded a considerable (}uantity of very good material, in part from 

 localities long since abandoned and hence of some prospective value. 

 These accumulations disposed of, attention Avas turned to the segre- 

 gation of all such minerals as have been the subject of special inves- 

 tigation or which represent the originiil materials upon which new 

 species or varieties have been founded, thus forming a collection 

 which corresponds to types in a paleontological series. 



The principal Avork on the petrographical collections has been the 

 breaking up and assorting of lots Avhich have been held for many 

 years as local collections. In cases where their usefulness as such no 

 longer exists, these have been condemned as sets, the more desirable 

 material held for incorporation in the study series, some held as 

 duplicate, and some discarded. 



Much attention has been devoted to the exhibition series in the 

 section of iuA^ertebrate paleontology. The collections illustrating 

 stratigraphic geology liaA'e been increased by large slabs illustrating 

 the occurrence of fossils in the matrix; the exhibits of rocks and 

 characteristic fossils illustrating the Archeozoic and Proterozoic eras 

 of geology have been completed ; and the preparation and installation 

 of specimens illustrating the cephalopods, echinoids, and other classes 

 in the biological series haA^e been continued. 



The Cambrian collections in the charge of Secretary Walcott have 

 been examined and rearranged by him personally, and the material 

 collected during his field season of 1919 has been recorded and Avorked 

 out, preliminary examination being giA^en the individual specimens. 

 Assistant Curator Resser has cared for the Cambrian material housed 

 in the Museum building. 



The Avork of identification and distribution into the biolooical 

 series of the unstudied material and the elimination of duplicates 

 has been continued. Many thousands of specimens huxe been han- 

 dled in this Avay during tlie year. These study collections are noAV 

 so extensive that much time must be devoted each 3^ear simply to the 

 manual labor iuAolved in providing space for neAv materials. The 

 past 3^ear has been no exception, as it has been necessary to rearrange 

 the three molluscan groups, cephalopods, pelecypods, and gastropods. 



Doctor Ulrich and his assistants have, as before, cared for the 

 extensiA^e series of Ozarkian and Canadian fossils, the higher divi- 

 sions of the Paleozoic remaining under the immediate care of the 

 curator. Mr. Frank Springer has devoted his time to the study of 

 the echinoderms, and Dr. T. AV. Stanton, Avith the aid of Mr. T. E. 

 .Williard, has continued his care of the Mesozoic series. 



