The next summer, an old professor, with a pair of spectacles on his nose and a great botanizing-case on his back, came roaming through the wood.  
He sat down under the crab-apple-tree to eat his lunch, but fell a-thinking in the middle of it, leant his head back against the trunk and looked up into the leaves.
 
Suddenly he jumped up, dropped his sandwich and stared hard at the mistletoe. He took off his spectacles, wiped them on the skirt of his coat, put them back on his nose and went on staring.
 
Then he ran in and fetched the old keeper:
 
"Keeper, do you see that tree?" he said. "That's the most tree in the whole wood."
 
"That one there?" said the keeper. "Why, it's only an old crab-apple-tree, professor. You should see a couple of apple-trees I have in my garden."
 
"I don't care a for them," said the professor. "I would give all the apple-trees in the world for this one tree. There's a mistletoe growing on her, you must know, and the mistletoe is the rarest plant in Denmark. You must put a fe............