In this case, Mentha is the genus and piperita is the species; (Ehr.) is the name of the botanist who originally classified the species, and Briq. (the abbreviation of Briquet) is the name of the person who approved the reclassification, thus there are no brackets.
Linnaeus classified this plant as Mentha piperita, but Ehrhart reclassified it as Mentha x piperita var. citrata; the x indicates that the plant is a cross between Mentha spicata and Mentha aquatica, and the 'var.' indicates that this is a variety of mint that isn't distinct enough to be classified as a separate species.
The family to which the plant belongs is Labiatae. Pinaceae, Abies alba Mill.
