Crustacean That Attaches to Boats and Animals
Puzzle 17 of Reach New Heights Pack
Question is: Crustacean That Attaches to Boats and Animals
and the answer is: BARNACLE
Word Meaning:
BARNACLE — A marine crustacean of the subclass Cirripedia that attaches itself to submerged surfaces such as tidal rocks or the bottoms of ships.
Definitions from Wiktionary.