frequently be seen floating round our coasts towards the end of the 

 summer. In the water they are almost invisible on account of the 

 extreme transparency of their bodies ; but if a muslin net be drawn 

 through the water from the stern of a boat, and the net then gently 

 turned inside out in a vessel of sea water, a number of medusoids 

 may be obtained for examination. These creatures produce eggs 

 which yield small ciliated larvae that swim about freely for a time, 

 and then settle down and establish stalked colonies as previously 

 described. 



The larger jelly-fishes or Medusae so frequently seen floating in 

 enormous numbers near the surface of the sea during the summer 

 months are allied to the medusoids. Their bodies are so soft that 

 it is a difficult matter to remove them from the water without 

 injury, 'and when removed their graceful forms are completely 

 destroyed by the pressure of their own weight. When left stranded 

 on the beach, as is often the case, they seem to dissolve almost 

 completely away, so readily does the soft animal tissue disintegrate 

 in the large proportion of water, which forms about 95 per cent, of 

 the weight of the whole body. 



Those who desire to examine the nature and movements of 

 the medusas will find it necessary to observe them in water. The 

 creatures may be lifted out of the sea in a vessel placed below them, 

 and then transferred to a glass tank or a still rock pool by 

 submerging the vessel and allowing them to float out. It will 

 then be observed that the mouth is situated at the summit of a 

 tube that projects from the middle of the under side of the ' bell,' 

 and is surrounded by lobed or frilled lips. Marginal tentacles also 

 generally fringe the edge of the bell, projecting downwards into the 

 water. Round the circumference of the body may be seen a 

 circular canal, from which several tubes converge towards, and 

 communicate with, the cavity of the stomach. 



When a medusa is inactive, its body gradually sinks to the 

 bottom, being usually slightly heavier than the water in which 

 it lives; but it is enabled to keep afloat by those rhythmic con- 

 tractions of the bell with which we are so familiar. It seems that 

 the medusae are very sensitive to various external conditions, for 

 they frequently disappear simultaneously from the surface water, 

 and as suddenly reappear in shoals when the conditions are more 

 favourable; but it is-difficult to understand the causes which give 

 rise to these remarkable movements. 



The medusae are often termed the AcalepTice a word which 



