136 



THE POPULAR EDUCATOR. 



SECTION LXVIII. CEPHALOTACE^E. 



The genus Ccphalotus, which Labillardiere placed amongst 

 the Rosaceoe, and which other authors have annexed to the Saxi- 

 frages, is considered by Dr. Lindley as being likely to be ulti- 

 mately classed by botanists as a sub-family of the natural order 

 Ranunculaceae, or Crowfoots. 



It is constituted by certain perennial plants of Australia, 

 having a abort subterraneous stem, and leaves united in a tuft, 

 and offering two distinct forms ; one form plane, oval oblong, 

 the other situated a little below the preceding, composed of a 

 petiole dilated into a pair of labiate expansions, the lower one 

 being large, hollowed out like a cup, the upper one smaller, flat, 

 and serving as a cover. The flowers are white and small ; the 

 calyx is free, six-partite, petaloid, valvate in aestivation, corolla 

 absent. The twelve stamens are inserted upon the border of 

 the tube of the calyx. The six ovaries are sessile upon a plane 

 receptacle, alternate with the sepals, uni-locular. uni- or bi- 

 ovulate. Ovules erect, reflesed. Fruit composed of sL: achaenia, 



arid soils, and remain fresh by reason of the humidity they 

 absorb from the air as well as the soil. Nearly all the moia- 

 ture thus absorbed is retained, because the surface of theso 

 plants allows but little transudation, very few stomata or 

 evaporating pores existing in its structure. All the Crassu- 

 lacece abound in a slightly saline aqueous juice containing malic 

 acid. On account of these constituents, the Crassulacece have 

 acquired some celebrity as medicinal agents. A few species are 

 edible. The purple stonecrop (Sedum Telephium), the white 

 stonecrop (Sedum album), and the yellow stonecrop (Scduv:, 

 reflexum), as well as the house-leek (Sedum sempervivum) , are 

 frequently employed for stimulating wounds ; the Mediterranean 

 CrassuZc possess similar qualities. The acrid ctonecrop (Sedum 

 acre), a plant which grows in sunny planes in England, contains 

 an acrid principle, in virtue of which it is rubefacient, or causes 

 a redness of the skin when externally applied, purgative and 

 emetic when administered interna'ly. The root of the rose- 

 I poented stonecrop (Sedum Rhodiola), so called from the circuit;- 

 stfcnco of its diffusing an odour similar to that of a rose. v:as 



218. CHAMPION'S RHODOLriv (KHODOLEIA CHAMPIOXI). 



219. COJIE-BI;AI::NG UEDOEHOG THISTLE (ECHINOCACTUS PECTIN IFEBCS), 



which open on their inner edge. Cotyledon small, straight, at 

 the base of a fleshy albumen. One species, the Ccphalotus 

 follicularis, or New Holland pitcher plant (Fig. 225, 226), has 

 been some years introduced into European gardens. 



SECTION LXIX. CRASSULACE-S:, OR HOUSE-LEEKS. 



Characteristics : Sepals free ; petals in number equal to 

 them, free or coherent at the base, imbricated in aestivation ; 

 stamens inserted with the petals and ordinarily adherent to 

 them ; their number equal to or double that of the petals ; 

 carpels free or attached to an axis, each furnished with a scale 

 at its base, and pluri-ovulate ; ovules horizontal or pendent ; 

 follicles ordinarily free ; iihiscence ventral, sometimes com- 

 bined into a capsule, in which case the dehiscence is dorsal ; 

 embryo dicotyledonous, straight, occupying the axis of a small 

 fleshy albumen. 



The Crassulacew are in some cases subligneous herbs, more 

 or less charged with juicy matter ; leaves ordinarily simple, de- 

 prived of stipules ; flowers terminal, corymbous, or in cymes, 

 or agglomerated, occasionally solitary (Fig. 221, 224). 



The Crassulacece grow in the warmer parts of the temperate 

 regions of the Eastern Hemisphere. They thrive in the most 



formerly used by medical practitioners and herbalists as a 

 sedative. The Greenlanders boil tlia vegetable, and eat it aa 

 a pot-herb. 



The leaves of Bryophyllumcalycinum, a species of house-leek, 

 a native of the East Indies, present a very curious physiological 

 phenomenon, the germs of this plant growing at the extremity 

 of the leaf-nerves. A single leaf laid on a damp surface will 

 throw out young plants all round its margin. 



. SECTION LXX. MESEMBEYACE^, OR FICOIDS. 



Characteristics : Tubular calyx consolidated with the ovary ; 

 petals indefinite, inserted on the calyx ; ovary many-celled, pla- 

 centa applied to the midrib of the carpels or axile ; ovules 

 numerous, curved ; stigmas sessile ; capsule multi-valvular ; 

 seed dicotyledonous ; embryo surrounding a farinaceous 

 albumen. 



The members of this natural order are herbs or small shrubs, 

 and are chiefly natives of the Cape of Good Hope. Their leaves 

 are fleshy, their flowers axillary or terminal, solitary, or disposed 

 in the form of a cymous corymb. Capsule at first fleshy, then 

 almost woody ; opening in a stellate manner. Epicarp thick 

 and coriaceous, peoarated from the endocarp, which latter is 



