xii CONTENTS 



CHAPTER PAGE 



VII. Parasitism, Commensalism, and Symbiosis on the 



Sea-shore 132 



Stages in Development of Intimate Associations, 133. Com- 

 mensalism, 135. Parasitism, 139. Symbiosis, 149. 



VTII. The Movements of Shore Animals . . . .152 

 The Problem of Locomotion on the Sea-shore, 152. Clamber 

 ing, 153. Gliding, 159. Swimming, 163. Burrowing, 165, 

 Boring, 167. Jumping, 171. Locomotion on Surface Film, 172 

 Migrations, 173. Vertical Movements in Relation to Tides, 175 

 Homing, 176. Retrospect, 178. 



IX, The Nutrition and Methods of Feeding of Shore 



Organisms 179 



The Problem in General, 178. Nutrition of Marine Plants, i8o 

 Nutrition of Marine Animals, 183. Putter's Theories, 185 

 Bacteria in the Sea, 187. The Problem in Particular, 188 

 Methods of Feeding in the different Groups, 190. Retrospect, 198 



X. Respiration in Shore Animals .... 



The Problem in General, 200. Accommodation of Water- 

 breathers to Breathing in Air, 205. Respiration in Relation to 

 Structure and Habit, 209. Respiration in Relation to Burrow- 

 ing, 211. Respiration in relation to Turbidity of Inshore 

 Waters, 213, Retrospect, 215. 



XT. The Nervous Organisation and Behaviour of Shore 



Animals 217 



Shore Animals as Subjects for Study of Behaviour, 217. Nervous 

 Organisation of various Shore Forms, 219. Reactions of Shore 

 Animals to their Environment, 229. Reactions to Light, 230. 

 Reactions to Moisture, 234. Reactions to Pressure or Contact, 

 235. Reactions to Gravity, 237. Rhythmic Behaviour, 239. 

 Characteristic Activities of Shore Forms, 241. Tube-building 

 in Polychasts, 241. Occupation of Gasteropod Shells by 

 Hermit Crabs, 243. Masking of Spider-Crabs, 244. 



XII, The Reproduction and Growth of Shore Animals . 246 

 Risks attending Reproduction on Shore, 246. Adhesive Spawn — 

 Protective Coverings, 246. Pelagic Larvae, 247. Spawning 

 places, 248. Adjustment of Life Cycle, 248. Parental Care, 252. 

 Nest-building, 255. Breeding and Growth of Common Shore 

 Forms, 258. Retrospect, 280. 



XIII. Some Economic Aspects of Shore Life . . . 282 



Importance of Sea-shore to Man, 282. Shore Animals utilised 

 by Man, 282, Bait, 288. Adverse Factors, 289. Plants of 

 Economic Value living within the Tidal Zone, 291. Injurious 

 Alg.'je, 297. Effects of Sewage, 298. Injurious Animals, 300. 

 Sea-shore and Human Culture, 300, 



APPENDICES 



I. Notes on some of the Commonest Shore Alg^ . . 303 



II. Shore Insects 308 



III, Illustration of a Method of surveying a Typical 



Piece of Sea-shore 312 



Bibliography ......... 315 



Indexes 325 



