Page 45 - One Million Things: Animal Life - The Incredible Visual Guide

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CHITONS These inhabitants of rocky shores have a flat shell made up of eight overlapping plates. At low tide, chitons cling tightly to rocks and, if pulled off, curl up into a protective ball. At high tide they creep slowly over rocks using their muscular foot and feed on algae and other small organisms by scraping them off the rocky surface with their radula. Blue (common) mussels

Chiton Valves of shell open to draw in water current
Textile cone shell Conus pertusus Found in both fresh water and the sea, bivalves include clams and mussels. Bivalves have a hinged shell with two pieces or valves. They breathe by drawing a current of water into their shell from which large gills extract oxygen. The gills also trap food particles that are

BIVALVES then transferred to the mouth, a process called filter feeding.

Cone shell paralyzes prey with its poisonous, harpoonlike radula Bright colors warn predators that the sea slug is poisonous
Troschel’s murex

Pair of nudibranch sea slugs

North’s long whelk Hooped whelk

soft-bodied whelk
Common limpet Spiral shell protects

slugs

TUSK SHELLS With shells that resemble miniature elephant’s tusks, these sea-dwelling mollusks are found offshore where they burrow into the seabed. The small eyeless head that emerges from the shell’s larger opening is surrounded by small tentacles. These sweep the seabed for tiny particles and draw them into the tusk shell’s mouth. GASTROPODS Most gastropods live in the sea. They have a head with eyes and tentacles, a muscular foot that produces creeping movements and all except the slugs have a large externa

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