2_~ 



PROCEEDINGS 



OF 



THE ROYAL SOCIETY. 

 Series B. Vol. 70. No. B 531 



BIOLOGICAL SCIENCES. 



CONTENTS. 



Page 



On the Combining Properties of the Opsonin of an Immune Serum. By 

 ROBERT MUIR, M.D., Professor of Pathology, University of Glasgow, 

 and W. B. M. MARTIN, M.B., Carnegie Research Scholar . . .187 



A General Consideration of the Subaerial and Fresh-water Algal Flora of 

 Ceylon. A Contribution to the Study of Tropical Algal Ecology. 

 Part I. — Subaerial Algae and Algae of the Inland Fresh-waters. By 

 F. E. FRITSCH, D.Sc, Ph.D., F.L.S., Assistant Professor of Botany, 

 University of London, University College . . . . . . *97 



Experiments made to determine the Conditions under which " Specific " 

 Bacteria derived from Sewage may be present in the Air of Ventilating 

 Pipes, Drains, Inspection Chambers and Sewers. By Major W. H. 

 HORROCKS, RA.M.C 255 



PRINTED FOR THE ROYAL SOCIETY AND SOLD B 

 HARRISON & SONS, 45, ST. MARTIN'S LANE, LONDON, 



Price Three Shillings. 



No. B 531. 



May 9, 1907. 



