REPORT OF THE SECRETARY 25 
Perry, associate in mineralogy, was published during the year as a 
- Bulletin of the National Museum. 
Dr. G. A. Cooper, in collaboration with Prof. A. S. Warthin, of 
Vassar College, completed his survey of Illinois Devonian oil strata, 
and, in collaboration with the Instituto Geolégico de México, con- 
tinued field and laboratory studies of the geology of northwestern 
Sonora. A month and a half of field work in Sonora, in association 
with his Mexican colleague, Ing. A. R. V. Arellano, resulted in note- 
worthy paleontological collections and considerable increase in knowl- 
edge of the structure and stratigraphy of the area. 
Under the Walcott fund of the Smithsonian Institution, in collabo- 
ration with Drs. Myron N. Cooper and R. S. Edmundson, of the Vir- 
ginia Geological Survey, Dr. Cooper made an investigation of the 
relationships of the limestones that occur on the flanks of Clinch 
Mountain in southwestern Virginia and northern Tennessee. 
Before his untimely death Dr. Charles E. Resser was engaged in the 
study of the Lower Ordovician trilobites of Vermont and adjacent 
areas and was continuing his Cambrian Summary and Bibliography. 
Many years of work by Drs. Walcott and Resser have gone into this 
summary and bibliography, both of which when finished will be valu- 
able contributions to science. 
Field work in vertebrate paleontology, usually one of the best sources 
of striking exhibition material, was necessarily restricted. In a 
short trip to the nearby Calvert Cliffs on Chesapeake Bay, Curator 
C. W. Gilmore and his assistants had the good fortune to excavate a 
sirenian skeleton of Miocene age, a fossil sea cow over 10 feet long. 
MISCELLANEOUS 
Visitors.—The number of visitors to the Museum buildings during 
the year showed an increase of 177,496 over the previous year. The 
total number, 1,532,765, is, of course, far below the peacetime record 
of 2,408,170 in 1937-38, but the increase does indicate a salutary up- 
trend in the degree to which the National Museum exhibits and col- 
lections are being viewed and studied by the people even in wartime. 
August 1943 and April 1944 saw the largest number of visitors, 162,016 
and 164,221, respectively, being recorded for these months. The 
attendance in the four Smithsonian and Museum buildings was as 
follows: Smithsonian building, 301,212; Arts and Industries building, 
566,496 ; Natural History building, 493,239; Aircraft building, 171,818. 
Since a considerable proportion of the visitors consisted of men and 
women in the armed forces, special services were proffered this group 
and every effort was made to enhance their visits. In the Natural 
History building a program of Sunday docent service, for guiding 
