Page 81 - Ultimate Visual Dictionary (DK)

EARLY SIGNS OF LIFE

Ambulacral groove
Row of Row of
ossicles ossicles
Small
ossicles
of upper Broad disk
surface
Central
disk
Short
arm
Iron
pyrites
FOSSILIZED STARFISH UPPER SURFACE OF LOWER SURFACE OF
FOSSILIZED STARFISH FOSSILIZED STARFISH

Jointed Chelicera Growing tip
leg (jointed
pincer)

Jointed leg
with oar-
shaped
paddle
Disk-shaped
sporangium
(spore-case)
Segmented
abdomen

UNDERSIDE OF FOSSILIZED EURYPTERID

Telson (tail
spine)
Leaflike scale

Abdominal
Shell contains eight segments
somites (thoracic
segments) Stem

Hingeless,
bivalved
shell
FOSSIL OF AN EXTINCT SHRIMP RECONSTRUCTION OF ASTEROXYLON

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