CONTENTS. 
XII. Observations on some Belemnites and other Fossil Remains of Cephalopoda, 
discovered by Mr. Reginald Neville Mantell, C.E. in the Oxford Clay near 
Trcmhridge, in Wiltshire. By Gideon Algernon Mantell, Esq., LL.D., 
F.R.S., F.L.S., Vice-President of the Geological Society .... page 171 
XIII. On the Structure of the Jaws and Teeth of the Iguanodon. By Gideon 
Algernon Mantell, Esq., LL.D., F.R.S., F.L.S., Vice-President of the Geo- 
logical Society, &^c 183 
XIV. Determinations of the Magnetic Inclination and Force in the British Provinces of 
Nova Scotia and New Brunswick, in the Summer of 1847 - By Professor 
George W. Keely, of Waterville College, Maine, United States. Communi- 
cated by Lieut. -Colonel Sabine, For. Sec. R.S 203 
XV. On a new Case of the Interference of Light. By the Rev. Baden Powell, M.A., 
F.R.S., F.R.A.S., F.G.S., Savilian Professor of Geometry in the University of 
Oxford 213 
XVI. On the Theory of certain Bands seen in the Spectrum. By G. G. Stokes, M.A., 
Fellow of Pembroke College, Cambridge. Communicated by the Rev. Baden 
Powell, M.A., F.R.S., 8^c 227 
XVII. An Experimental Inquiry undertaken with a view of ascertaining whether any, 
and what signs of current Electricity are manifested during the organic process 
of Secretion in living animals, being an attempt to apply some of the discoveries 
of Faraday to Physiology . By H. F. Baxter, Esq. Communicated by Sir 
Benjamin Brodie, Bart., F.R.S. 243 
XVIII. On the Direction assumed by Plants. By Professor Macaire of Geneva. 
Communicated by V.M. Roget, M.D., Sec. R.S 253 
XIX. Microscopical Examinatioji of the Contents of the Hepatic Ducts, with con- 
clusions founded thereon as to the Physiological signification of the Cells of 
Hepatic Parenchyma, and as to their Anatomical relation to the Radicles of the 
Hepatic Ducts. By T. Wharton Jones, F.R.S 277 
Index 281 
Appendix. 
[ 1 ] 
Presents 
