Contents. v 



PAGE. 



VI. The Permeability of Cells for Acids. By E. NEWTON HARVEY . . . 143-156 



VII. Medusae of the Philippines and of Torres Straits. By A. G. 



MAYER. 3 plates, 7 text-figures 157-202 



Introduction 159 



Structure, Physiology, Habits, and Development of the Scypho- 



medusse 162 



Part I. Scyphomedusse of the Philippine Islands 170 



Description of Species 170 



Part II. Hydromedusse of Torres Straits, Australia 199 



Description of Species 199 



VIII. Report on the Bahama Cerions Planted on the Florida Keys. 



By PAUL BARTSCH. 8 plates 203-212 



New Colonies started on the Florida Keys in 1914 209 



Observations on the Adult Specimens of the first generation of 



Florida-born Individuals 209 



The "White House Type" 210 



The "King's Road Type" of Cerions 212 



IX. Structure and Polarity of the Electric Motor Nerve-cell in Tor- 



pedoes. By ULRIC DAHLGREN. 6 plates, 6 text-figures. 213-256 



Nucleus 221 



Literature 230 



Account of the Experiments 232 



Summary and Conclusions 251 



Bibliography 253 



Explanation of Plates 255 



