Viola odorata L.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Species Description - Finely hairy, with a long-creeping rhizome and spreading by numerous leafy stolons rooting at the nodes; lvs broadly ovate to orbicular, 2–6 cm, rounded or obtuse at the tip, evenly crenate, cordate at base, peduncles equaling or shorter than the lvs; fls very fragrant, typically deep violet, varying to white, the lateral pet usually bearded; style recurved-hooked at the tip; sep ciliate; ovary and fr hairy; cleistogamous fls on recurving peduncles, with broadly ovoid, hairy, purplish fr; seeds large, ochroleucous; 2n=20. Native of Europe, cult. in many forms and often escaped, especially about dwellings. Apr., May.