THE SMITHSONIAN INSTITUTION XHI 



ASTROPHYSICAL OBSERVATORY 



Director. — Charles G. Abbot, 

 Assistant director. — Loyal B. Aldeich. 

 Research oss/.s/cjii.— Frederick E. Fowle, Jr. 

 Associate research assistant. — William H. Hoover. 



DIVISION OF RADIATION AND ORGANISMS 



Chief. — Frederick S. Br.\ckett. 

 Research associate. — Earl S. Johnston. 

 Associate research assistant. — B. D. McAlister. 

 Research assistant. — Leland B. Clark. 



REGIONAL BUREAU FOR THE UNITED STATES, INTERNATIONAL 

 CATALOGUE OF SCIENTIFIC LITERATURE 



Assistant in charge. — Leonard C Gunnell. 



