The Comb Jellies and Others 77 



in the case of jellyfishes, will be made clear in what 

 follows. 



The large jellyfishes, or medusae, as they are also 

 called because of their tentacles which are suggestive 

 of the Gorgon's locks, range from the size of a mere 

 speck to several feet in diameter. But however di- 

 verse may be their dimensions, they all agree in general 



pelagia; a jellyfish. 



outlines and plan of structure. They are umbrella- 

 shaped, or, rather, they are roughly comparable to a 

 mushroom in which the stalk is superseded by depend- 

 ent central organs, the mouth and stomach of the ani- 

 mal. As in the case of the comb jellies, many of the 

 jellyfishes are phosphorescent; sofne are luminous over 

 the entire body, others have light-producing organs of 

 a more restricted type; and, also, like the ctenophores, 

 they inhabit all seas. 



