Peppermint
Mentha piperita. Mint Family.
Leaves.--Opposite; aromatic; with leaf-stems; sharply toothed; pungent-tasting. Flowers.--Small; purple or whitish; in loose, narrow, interrupted leafless spikes; otherwise as in above.
The peppermint is another European emigrant, and an escape from gardens, which has made itself thoroughly at home along our brooks.