Both Hatter and March Hare are characters in the book Alice's Adventures in Wonderland.
The Hatter is a fictional character in Lewis Carroll's "Alice's Adventures in Wonderland" and its sequel "Through the Looking-Glass". 
The March Hare (called Haigha in "Through the Looking-Glass") is a character most famous for appearing in the tea party scene in Lewis Carroll's "Alice's Adventures in Wonderland". 
