PLANTS: Slender perennial herbs. LEAVES: opposite with interposed stipules. FLOWERS: 4-5-merous, in loose forking terminal cymes; corolla funnelform; ovary 2-loculed, each locule with 1 ovule. FRUIT: splitting at maturity into 2 closed mericarps. NOTES: 2 spp. w N. Amer. and China. (for Albert Kellogg). REFERENCES: Terrell, Edward E. 1995 Rubiaceae. Houstonia. J. Ariz. - Nev. Acad. Sci. 29(l): 36.