An arboreal animal which makes itself at home in genealogical trees.

A mysterious form of matter secreted by the brain. Its chief
activity consists in
the endeavor to ascertain its own nature, the futility of the attempt
being due to the fact that it has nothing
but itself to know itself with. From the Latin mens, a fact unknown
to that honest shoe-seller, who, observing that his learned competitor
over the way had displayed the motto ”Mens conscia recti,”
emblazoned his own front with the words ”Men’s, women’s and children’s
conscia recti

The Devil’s Dictionary by

Ambrose Bierce).