Physostegia
(from physa, a bladder, and stege, a covering; alluding to the inflated calyx). False Dragon-head. ORD. Labiatae. A genus consisting of only three species of hardy, tall, erect, glabrous, or very slender and puberulous herbs, confined to North America. Flowers flesh-colour or purple, sessile; calyx tubular-campanulate. Sub-equally five-toothed, becoming inflated at fructescence; corolla tube long, exserted; upper lip erect, entire or emarginate, the lower one spreading and trifid; whorls two-flowered, secund, densely or interruptedly spicate; spikes solitary, or often many, at the tips of the branches, sub-paniculate. For culture, see Dracocephalum. P. imbricata (imbrieated). A synonym of P. virginiana speciosa. P. intermedia (intermediate). fl., corolla five to six lines long, much dilated upwards; spikes filiform, commonly rather remotely flowered. Summer. l. linear-lanceolate, repand-denticulate. Stem slender, remotely leaved, 1ft. to 3ft. high.
P. parviflora (small-flowered). fl. corolla rather narrow, 1/2in. long; spikes short, 1in. to 4in. long. Summer. l. lanceolate or ovate-lanceolate, denticulate. Stem rather slender, leafy, 1ft. to 2ft. high. 1825. P. virginiana (Virginian).* fl. flesh-coloured or purple, about 1in. long, nearly sessile, approximate or distant; racemes terminal, simple, or paniculately branched. July to September. l. thickish, sessile, usually lanceolate, sometimes oblong-ovate or obovate, usually acute, irregularly and acutely serrated, narrowed at base, green on both surfaces. Stems erect, herbaceous. h. 1 1/2ft. to 4ft. 1683. A variable species. SYNS. Dracocephalum variegatum, D. virginianum (B. M. 467).
P. v. denticulata (slightly-toothed). fl. in a more slender or loosely-flowered spike. l. crenulate-denticulate or obscurely serrated. A more slender and commonly low form. SYN. Dracocephalum denticulatum (B. M. 214). P. v. obovata (obovate). l. oblong or obovate, often obtuse. P. v. speciosa (showy).* fl. in dense, paniculate spikes. l. lanceolate, very acutely serrated. SYNS. P. imbricata (B. M. 3386), Dracocephalum speciosum, of Sweet (S. B. F. G. 93).