122 ANNUAL. REPORT SMITHSONIAN INSTITUTION, 1923 



The diameters of the stars, by A. Danjon. 



Isotopes and atomic weights, by F. W. Aston. 



Modifying our ideas of nature: The Einstein theory of relativity, by Henry 



Norris Russell. 

 The alkali problem in irrigation, by Carl S. Scofield. 

 An outline of geophysical-chemical problems, by Robert B. Sosman. 

 The yielding of the earth's crust, by William Bowie. 

 The age of earth, by the Right Hon. Lord Rayleigh, W. J. Sollas, J. W. 



Gregory, and Harold Jeffreys. 

 The department of geology of the U. S. National Museum, by George P. Merrill. 

 Some observations on the natural history of Costa Rica, by Robert Ridgway. 

 The historic development of the evolutionary idea, by Branislav Petronievics. 

 The heredity of acquired characters, by L. Cuenot. 



Breeding habits, development, and birth of the opossum, by Carl Hartman. 

 Some preliminary remarks on the velocity of migratory flight among birds, 



with special reference to the Palaearctic region, by R. Meinertzhagen. 

 A botanical reconnaissance in southeastern Asia, by A. S. Hitchcock. 

 Ant acacias and acacia ants of Mexico and Central America, by W. E. Safford. 

 The fall webworm, by R. E. Snodgrass. 

 Collecting insects on Mount Rainier, by A. L. Melander. 

 The science of man : Its needs and prospects, by Karl Pearson. 

 Pigmentation in the old Americans, with notes on graying and loss of hair, 



by AleS Hrdlic"ka. 

 Ancestor worship of the Hopi Indians, by J. Walter Fewkes. 

 The Indian in literature, by Herman F. C. Ten Kate. 

 Leopard men in the Naga Hills, by J. H. Hutton. 

 A new era in Palestine exploration, by Elihu Grant. 

 The alimentary education of children, by Marcel Labbg. 

 A fifty-year sketch history of medical entomology, by L. O. Howard. 

 Laid and wove, by Dard Hunter. 

 Lead, by Carl W. Mitman. 

 William Crawford Gorgas, by Robert E. Noble. 



REPORT FOR 1922 



The report of the executive committee and proceedings of the 

 Board of Regents of the Institution, and the report of the secretary, 

 both forming part of the annual report of the Board of Regents to 

 Congress, were issued in pamphlet form in December, 1922. 

 Report of the executive committee and proceedings of the Board of Regents 



of the Smithsonian Institution for the year ending June 30, 1922. 10 pp. 



(Publ. 2710.) 

 Report of the Secretary of the Smithsonian Institution for the year ending 



June 30, 1922. 125 pp. (Publ. 2709.) 



The general appendix to this report, the manuscript of which 

 went to the Government Printing Office a few days after the close 

 of the fiscal year, contains the following articles : 



Who will promote science? by C. G. Abbot. 



Recent discoveries and theories relating to the structure of matter, by Karl 

 Taylor Compton. 



The architecture of atoms and a universe built of atoms, by C. G. Abbot. 



Aeronautic research, by Joseph S. Ames. 



Photosynthesis and the possible use of solar energy, by H. A. Spoehr. 



