Answer:
Thirty men and ladies two, gathered for a festive do; Dressed quite formal, black and white; soon movement turned to nasty fight.
I grow where no flower grows, where no light touches the walls, up or down, that I don't care, was here before people were.
When it comes in, From sea to shore, Twenty paces you'll see, No less, no more.
What word looks the same upside down and backwards?
Describes universities like Harvard and can be poisonous.
If it’s information you seek, come and see me. If it’s pairs of letters you need, I have consecutively three. What am I?