CONTENTS 
PAGE 
Officers and Members of the Academy vii 
Notices of Biographical Memoirs 54 
Report of the Annual Meeting, April, 1918 261 
Award of Medals 273 
Research Grants from the Trust Funds of the Academy 273 
Index 419 
NATIONAL RESEARCH COUNCIL 
Report of the Committee on Anthropology 52 
Meetings of the Executive Committee 76 
Minutes of Executive Board of War Organization 122 
Executive Order Issued by the President of the United States, May 11, 1918. . 251 
Minutes of the Second Meeting of the Executive Board of the War Organi- 
zation in Joint Session with the Council of the National Academy of 
Sciences 252 
Minutes of Third Meeting of Executive Board of War Organization 256 
Minutes of the Meeting of the Executive Board 397, 405 
Minutes of Joint Meeting of the Executive Board and the Council of the 
National Academy of Sctences 410 
Minutes of the Meeting of the Executive Board 414 
MATHEMATICS 
Invariants which are Functions of Parameters of the Transformation 
By Oliver E. Glenn 145 
On the Representation of a Number as the Sum of any Number of Squares 
and in Particular of Five or Seven By G. H. Hardy 189 
Arithmetical Theory of Certain Hurwitzian Continued Fractions 
By D. N. Lehmer 214 
On Closed Curves Described by a Spherical Pendulum By Arnold Emch 218 
On the ck-Holomorphisms of a Group By G. A. Miller 293 
Invariants and Canonical Forms By E. J. Wilczynski 300 
On Certain Projective Generalizations of Metric Theorems, and the Curves 
of Darboux and Segre By Gabriel M. Green 346 
On Jacobi's Extension of the Continued Fraction Algorithm. . .By D. N. Lehmer 360 
A Characterization of Jordan Regions by Properties Having No Reference to 
their Boundaries By Robert L. Moore 364 
ASTRONOMY 
The Location of the Sun's Magnetic Axis 
By F. H. Seares, A. van Maanen, and F. Ellerman 4 
The Rotation and Radial Velocity of the Central Part of the Andromeda 
Nebula By F.G. Pease 21 
A Determination of the Solar Motion and the Stream Motion Based on Radial 
Velocities and Absolute Magnitudes By Gustaf Str timber g 36 
Dependence of the Spectral Relation of Double Stars upon Distance 
By C. D. Perrine 71 
iii 
