666 ANNUAL EEPOET SMITHSONIAN" INSTITUTION, 1917. 



United States and spent several months in an extended trip through 

 Russia and its Provinces. In 1906 he spent the summer on an ex- 

 pedition to central Alaska, visiting the region to the north of Prince 

 William Sound. He traveled extensively in western America and 

 Mexico, reaching distant portions of the western Sierra Madre dis- 

 trict. 



With the outbreak of the war Professor Clark became actively in- 

 terested in problems of defense and economic preparedness. Pie was 

 appointed a member of the National Research Council and was 

 chairman of the subcommittee on road materials and a member of 

 the committee on camp sites and water supplies. He was also chair- 

 man of the committee on highways and natural resources of the 

 Maryland Council of Defense. 



Professor Clark made numerous contributions to geological litera- 

 ture, his work being confined largely to the Cretaceous and Tertiary 

 formations of the Atlantic Coastal Plain and the Carboniferous de- 

 posits of the central Appalachian region. Professor Clark's chief 

 paleontological interest was centered in the Echinoidea, to the eluci- 

 dation of which group he published several monographs. One of his 

 monuments will be the series of reports 'of the Maryland Geological 

 Survey, which set a new standard for State publications both as to 

 subject matter and bookmaking. The systematic reports in which 

 he was most interested will be of perennial service to science. 



He was a member of numerous clubs, including the University, 

 Maryland, of which he was a vice president, Baltimore County, 

 Johns Hopkins, and City Clubs of Baltimore and the Cosmos Club 

 of Washington. 



He was married October 12, 1892, to Ellen Clarke Strong, daugh- 

 ter of the late Edward A. Strong, of Boston, and had four children, 

 Edward Strong, Helen, who was recently married to Capt. H. Find- 

 lay French, Atherton, and Marion, all of whom survive him. 



Professor Clark's administrative ability and professional attain- 

 ments are largely responsible for the extensive development of Mary- 

 land's mineral resources, and his loss will be severely felt in all quar- 

 ters. He was always keenly interested in the educational value of 

 the work of the various State bureaus which he directed and had 

 just finished writing a geography of Maryland for school-teachers. 

 At the time of his death he was engaged in writing a report on the 

 underground waters of the State and another on the coals. 



