CALLIRHOE (of mythological origin, from Callirhoe, a daughter of the river-god Achelous). Poppy-Mallow. Allied to Malva. Species belonging to this genus have been erroneously referred to Malva and Nuttallia. ORD. Malvaceæ. A genus of elegant annual or perennial herbs, natives of North America. They are of extremely easy cultivation, thriving in a compost of light, rich, sandy loam. Propagation of the perennial species may be effected by means of both seeds and cuttings; of the annuals, by seeds only. Seeds should be sown in spring, either outside, or in pans in a cold frame. Young cuttings should be taken and dibbled in sandy soil in a frame.

C. digitata (fingered).* fl. reddish-purple; peduncles long, axillary, one-flowered. Summer. l. sub-peltate, six to seven-parted, with linear-entire or two-parted segments; upper ones more simple. h. 2ft. to 3ft. 1824. Perennial. (S. B. F. G. 129, under the name of Nuttallia digitata.)

C. involucrata (involucrate).* fl. crimson, nearly 2in. across, loosely panicled. Summer. l. divided nearly to the base, three to five-parted; segments narrow, lanceolate, three to five-toothed, hairy on both surfaces. Habit procumbent; stems hairy. h. 6in. Perennial. (G. W. P. A. 26.) SYN. Malva involucrata (B. M. 4681).

C. Papaver (Poppy-like).* fl. violet-red; sepals ovate-acute, ciliated. Summer. l., root leaves lobed or pedate; lower stem leaves palmato-pedate, upper digitate or simple. h. 3ft. Louisiana, 1833. Perennial. SYN. Nuttallia Papaver. (B. M. 3287.)

C. pedata (pedate-leaved). fl. cherry-red, panicled. August. l. laciniately-pedate; upper ones trifid. h. 2ft. to 3ft. 1824. Annual. (R. H. 1857, 148.)

C. triangulata (triangular-leaved). fl. pale purple. August. 1836. Perennial. SYN. Nuttallia cordata (under which name it is figured in B. R. 1938).

CALLISTACHYS. See Oxylobium.

CALLISTEMMA. See [Callistephus].

CALLISTEMON (from kallos, beauty, and stemon, a stamen; in most of the species, the stamens are of a beautiful scarlet colour). ORD. Myrtaceæ. Handsome greenhouse evergreen shrubs or trees, having the inflorescence rising from the old branches in crowded spikes, as in the species of Melaleuca, but with the stamens free, as in Metrosideros. Leaves elongated, stiff, alternate, usually lanceolate. All the species of this genus are very ornamental and neat in habit. They are well adapted for a conservatory. The soil best suited for them is a mixture of loam, peat, and sand. Ripened cuttings strike root in sand, under a hand glass; seeds are frequently produced on large plants, and these may also be used to increase the stock, but they do not produce flowering plants for a considerable time; whereas plants raised from cuttings, taken from flowering plants, come into flower when small.

C. linearis (linear-leaved).* fl. scarlet; calyces clothed with velvety pubescence. June. l. linear, stiff, acute, keeled beneath, channelled above, villous when young. h. 4ft. to 6ft. New South Wales, 1788.

C. lophanthus (crest-flowered). Synonymous with C. salignus.

C. salignus (willow). fl. straw-coloured, distinct, spicate, nearly terminal; petals rather pubescent, ciliated; calyx pilose. June to August. l. lanceolate, attenuated at both ends, mucronate, one-nerved, villous when young, as well as the branches. h. 4ft. to 6ft. Australia, 1806. SYN. C. lophanthus. (L. B. C. 1302.)

C. speciosus (showy).* fl. scarlet; calyx villous. March to July. l. lanceolate, mucronate, flat, middle nerve rather prominent; when young, rather silky from adpressed villi, and reddish. h. 5ft. to 10ft. West Australia, 1823. SYN. Metrosideros speciosa. See Fig. 327. (B. M. 1761.)

FIG. 327. CALLISTEMON
SPECIOSUS.

CALLISTEPHUS (from kallistos, most beautiful, and stephos, a crown; in allusion to the appendages on the ripe fruit). China Aster. SYN. Callistemma. ORD. Compositæ. A hardy annual, requiring an open situation and a rich loamy soil. Involucre of many fringed bracts; receptacle naked, pitted; pappus double. Propagated by seed, sown in a hotbed in March, the seedlings being hardened off and transplanted in May. For culture of these much grown plants and their varieties, see [Aster.]