- Group 1Lycophytes, Monilophytes
- Group 2Gymnosperms
- Group 3Monocots
- Group 4Woody angiosperms with opposite or whorled leaves
- Group 5Woody angiosperms with alternate leaves
- Group 6Herbaceous angiosperms with inferior ovaries
- Group 7Herbaceous angiosperms with superior ovaries and zygomorphic flowers
- Group 8Herbaceous angiosperms with superior ovaries, actinomorphic flowers, and 2 or more distinct carpels
- Group 9Herbaceous angiosperms with superior ovaries, actinomorphic flowers, connate petals, and a solitary carpel or 2 or more connate carpels
- Group 10Herbaceous angiosperms with superior ovaries, actinomorphic flowers, distinct petals or the petals lacking, and 2 or more connate carpels
See Cantino and Wagstaff (1998) for circumscription of this genus. Clinopodium nepeta (L.) Kuntze was reported from RI by George (1992), but specimens are unknown.
1b. Verticillasters with numerous flowers in dense clusters at the stem tip and 1–3 of the upper axils, each flower subtended by ciliate, linear-subulate bracts about as long as the calyx [Fig. 691]; calyx glabrous inside the connate tube; plants perennial from short stolons, 20–50 cm tall
Show photos of: Each photo represents one species in this genus.