CONTENTS. 
(B.) 
VOL. 180. 
I. On the 'present Position of the Question of the Sources of the Nitroyeii of Vegetation, 
ivith some new Results, and prelmiinary Notice of new Lines of Investigation. 
By Sir J. B. Lawes, Bart., LL.D., F.R.S., and Professor J. H. Gilbert, 
LL.D., F.R.S .1 
II. On the Secretion of Saliva, chiefly on the Secretion of Salts in it. By .J. N. 
Langley, M.A., F.R.S., Fello'w of Trinity College, and H. M. Fletcher, B.A., 
Trinity College, Cambridge .109 
III. On the Organisation of the Fossil Plants of the Coal-Measures. —Part XV. By 
William Crawford Williamson, LL.D., F.R.S., Professor of Botany in the 
Owens College, Manchester .155 
IV. On the Electromotive Changes connected with the Beat of the Mammalian Heart, 
and of the 'Human Heart in particular. By Augustus D. Waller, M.D. 
Communicated by Professor Burdon Sanderson, A. A.6'..169 
V. On the Organisation of the Fossil Plants of the Coal-Measures. —Part XVI. By 
W. C. Williamson, LL.D., F.R.S., Professor of Botany in the Owens College, 
Manchester .195 
VI. Researches on the Structure, Organization, and Classification of the Fossil 
Rep)tilia. —VI. On the Anomodont Reptilia and their Allies. By H. G. 
Seeley, F.R.S., Professor of Geography in King's College, London . . 1115 
