[ iv ] 
V’l. Mathematical Cordrihutions to the Theory of Evolution. — YI. Genetic [Repro¬ 
ductive) Selection: Inheritance of Fertility in Alan, andv of Fecundity in 
Thoroughbred Racehorses. By Kael Peaesox, F.R.S., Alice Lee, B.A , 
B.Sc., and Leslie Beamley-Mooee .page 25/ 
VII. Ionic Velocities. By Oeme Massox, 31.A., D.Sc., Professor of Chemistry in 
the University of Melbourne. Communicated by Professor AY. Bamsay, 
F.R.S . 331 
V"IIL lyiemoir on the Theory of the Partitions of Numbers .-—Part IL By Alajor P. 
A. MacMahox, R.A., D.Sc., F.R.S . 351 
IX. On the Condensation Nuclei prodniced in Gases by the Action of RUntgen Rays, 
Uranium Rays, Ultra-violet Light, and other Agents. By C. T. Pv. AA^ilsox', 
AT.A., Cleric-Alaxivell Student in the University of Cambridge. Communi¬ 
cated. by Professor J. J. Tho:‘.isox', F.R.S. . 403 
X. Die Thermcd Deformation of the Crystcdlised Normcd Sulphates of Potassium, 
Rubidium, and Ca-sium. By A. E. Tuttox, B.Sc. Communicated by 
Captain Abxey, C.B., F.R.S . 455 
XL On the Electrical Conductivity of Flames Contedning Scdt Vapours. By 
Haeold a. AYilsox', B.Sc. [Bond, and Vic.), 1851 Exhibition Scholar, 
Cavendish Laboratory, Cambridge. Communicated, by Professor J, J, 
Thomsox, F.R.S. .. . 499 
Index to Volume . 529 
Errata 
531 
