550 THE INHABITANTS OF THE SEA. 
of the bell, and thus concentrating its efforts upon a narrower 
space. More or less numerous tentacles generally depend from 
the margin, and around it are disposed two kinds of remarkable 
bodies—* vesicles ” and “ pigment spots,” or “ eye-specks ”— 
which are supposed to be able to communicate the impressions 
of light and sound. This complexity of organisation in crea- 
tures which Réaumur contemptuously styled mere lumps of 
animated jelly is all the more wonderful when we consider that 
they consist almost entirely of water, and shrink to a mere 
nothing when abandoned by their vital power. Thus of a 
medusa originally weighing many pounds but few traces remain 
Various forms of Meduside. 
@ Aequorea formosa, scen in profile. 5b. Thesame, viewed from above. c. Upper view of Willsta 
stellata. d. Slabberia comca. e. Portion of the marginal canal of Traropsis Pattersunit. 
f. Polypite of Bougainvillea dinema. g. Part of its marginal canal. h. Steenstrupia Owenii. 
(a, 6, and d are about the natural size ; the others are magnified. ) 
after death ; the ground is covered with a light varnish ; all the 
rest has been absorbed by the thirsty sands. 
The oceanic or free-swimming forms of the Lucernaridz 
resemble the Meduside by their bell-shaped umbrella, but 
differ from them by their internal structure, by the absence of 
a marginal veil, by the nature of their canal system and mar- 
ginal bodies, and by their mode of development. The radiating 
canals, never less than eight in number, send off numerous 
branches, which form a very intricate network, and the vesicles 
