[ iv ] 
XXII. On the Placentation of the Lemurs. By William Turner, M.B. ( Lond .), Pro- 
fessor of Anatomy in the University of Edinburqh. Communicated by Professor 
Huxley, Sec.B.S page 569 
XXIII. Experiments on the Friction between Water and Air. By I)r. Viktor von Lang, 
Professor of Physics in the University of Vienna. Communicated by N. S. Mas* 
kelyne, M.A., F.B.S., Professor of Mineralogy in the University of Oxford. 589 
XXIV. On the Structure and Development of the Skull in the Batrachia. — Part II. 
By William Kitchen Parker, F.B.S 601 
XXV. On determining the Depth of the Sea without the use of the Sounding-line. By 
C. William Siemens, F.B.S. , D.C.L., Mem.Inst.C.E. 671 
XXVI. Electrodynamic Qualities of Metals (continued from Phil. Trans. Vol. 146. 
Lead Feb. 28, 1856). — Part VI. Effects of Stress on Magnetization. By Sir 
William Thomson, F.B.S. &c . , 693 
XXVII. On the Mature of the Force producing the Motion of a Body exposed to Bays 
of Heat and Light. By Arthur Schuster, Ph.D., Demonstrator in the Physical 
Laboratory of Owens College. Communicated by Balfour Stewart, F.B.S. 715 
XXVIII. On the Forces caused by the communication of Heat between a Surface and a 
Gas ; and on a New Photometer. By Professor Osborne Reynolds. Commu- 
nicated by B. Stewart, F.B.S., Professor of Natural Philosophy in Owens 
College, Manchester . 725 
Index 737 
