"Very good, Seamus! Not bad for a first try!" Lupin coughed as he

fanned away the silver puff of smoke left by Finnegan's exploding

patronus. "I'm sure that would give any Dementor pause!"

Several other students conjured up various silvery entities, some of

which had a lot of potential. Then it was Hermione's turn.

"Expecto Patronum!" Hermione shouted, as a beautiful purple dragon

sprang from her wand.

"Well done, Hermione!" Lupin beamed as the class applauded.

"Why is Hermione's patronus coloured? Isn't it supposed to be silver?"

Ron whispered to Harry.

Harry shrugged. "I don't think the Dementors will notice."