Vlll CONTENTS. 



CHAPTER IV. 



NOCTILUCA. 



A ramble and a scramble. Luminosity of the sea. Explana- 

 tion of this phenomenon. Structure of Noctiluca. Multi- 

 tudes in which they exist, Utility of phosphorescent 

 light p. 43-51 



CHAPTER V. 



ON MEDUSAE, OR " JELLY-FISHES." 



How to catch Medusae and submit them to microscopic exa- 

 mination. Habits of the Medusas. Their property of sting- 

 ing. Luminosity of the Medusas. Cause of their phospho- 

 rescence. Their unfitness for manure. Account of a mon- 

 ster. Description of Turns neglecta. Stomobrachium octo- 

 costatum described by the Rev. D. Landsborough. Sarsia 

 gemmifem produces progeny from buds. Reproduction of 

 Sarsia prolifera p. 52-67 



CHAPTER VI. 



HYDRA TUBA. 



History of the Hydra tuba. Its habits and mode of catching 

 prey. Propagation by buds. Formation of new colonies. 

 Reproduction by offshoots p. 68-75 



CHAPTER VH. 



HOW THE MEDUSA PRODUCES A HYDRA TUBA. 



Puzzling history of Medusae. Offspring of Medusa chrysaora. 

 Planulse. Origin QiHydra tuba. Most convenient method 

 of observation p. 76-81 



CHAPTER VIH. 



HOW THE HYDR.E TUBJE PRODUCE MEDUSJE. 



Formation of "Strobila." Brealnng up of "Strobila" into 

 Medusas. Observations of Sir John Dalyell. Deductions. 



p. 82-89 



