This southeastern species is most frequent in mesic woods of southern Appalachian regions. There are also scattered populations across southeastern states. See M and Chester (1991) for review of old, obscure or misleading records. A remarkable narrow western extension occurs on slopes and terraces along the Tennessee Rv. down to its mouth in Ky. (K). R. Dunlap (pers. comm.) has recently discovered this species on loess bluffs along the Mississippi Rv. in CARL and HICK. Halesia is also known locally from se. Ohio (Co) and s. W.Va. (HFG). The record from ne.Ky. in LAWR is an 1830s coll. of C.W. Short (with locality "Louisa" at Univ. of Tex.). Presumed colls. from HARL (B: Big Black Mt., "mesophytic north face woods, rare") and MCRE (Little 1971) have not been relocated, and the species is unknown from adjacent counties of Va. C. Benda (pers.comm.) has recently reported one small tree from near Cumberland Falls in WHIT, but perhaps in a planted location. Var. monticola (Rehd.) Reveal & Seldin may be a reasonable segregate at higher elevation in the southern Appalachians, up to 20-40 m tall, with generally larger leaves and larger flowers (W); it might be expected in HARL. Typical tetraptera is generally no more than 10 m tall. The trees in western Ky. reach about 25 cm in diameter and 10 m tall. H. carolina L., sensu stricto, is largely restricted to the Coastal Plain and Piedmont (K, W), but it has been combined with tetraptera by some authors (e.g. FNA 8). Reports of carolina from Ky. are based on this synomomization.