xll Illustrations 



PAGE 



Free-swimminy; larvit' of the moon snail (greatly enlarged) . 43 



Littorina ; a periwinkle shell 48 



Asterias; the common starfish. This individual is growing a 



new arm in the place of one that was lost 51 



Starfish searching for food (photograph taken on the bot- 

 tom of a tide pool) 68 



Bolina; a phosphorescent comb jelly (photograph taken in 



the water) 73 



Pleurobrachia ; the comet jelly 75 



Pelagia ; a jellyfish 77 



Disk of a dried jellyfish. A transparent film through which 

 type easily can be read is all that remains after exposure to 



the sun and air 78 



Strobila of Aurelia 83 



Polynoe; the scale worm 88 



Male hermit crab removed from his shell; showing the soft 



unarmored hind body 91 



Hermit crab in a broken shell. The disintegrating shells they 

 sometimes use leave portions of their bodies exposed to the 



attack of enemies 94 



Hermit crabs fighting (photograph taken in the water) . 99 



Courtship of the hermit crab (photograph taken in the water) 105 



Male and female hermit crabs. The female is the smaller 



creature perched on the larger shell of the other . . . 107 



Sargassum; the gulfweed 121 



Lessonia; a laminarian seaweed 121 



Egregia; a laminarian seaweed 122 



Macrocystis; a laminarian seaweed 123 



Enteromorpha ; a green seaweed 124 



Ulva; the sea lettuce 126 



Fucus, an olive-green seaw^eed, growing on a rock . . . 128 



Corallina; a red seaweed which resembles coral .... 133 



