THE POLYPETALOUS ORDERS. 389 



of five regular petals, withering and persistent, convolute in aestiva- 

 tion. Stamens as many as the petals and alternate with them, or 

 sometimes two to three times as many, distinct, withering ; anthers 

 extrorse. Styles three to five, distinct or nearly so, and each two- 

 parted (so as to be taken for ten styles, Fig. 390), with the divis- 

 ions sometimes two-lohed or many-cleft at the apex ; sometimes 

 all united into one. Fruit a one-celled capsule, opening loculici- 

 dally by three to five valves, with three to five parietal placentae ; 

 in Dionaea membranaceous and bursting irregularly, with a thick 

 placenta at the base. Seeds usually numerous. Embryo small, 

 at the base of cartilaginous or fleshy albumen. Ex. Drosera, the 

 Sundew ; and Dionsea (Fig. 228), so remarkable for its sensitive 

 leaves, which suddenly close when touched. 



723. Subord, Parnassieae consists of the genus Parnassia (belong- 

 ing to the northern temperate and frigid zones, and to the high 

 mountains of tropical Asia) ; which differs from Droseracea3 in the 

 want of glandular hairs, in the introrse anthers, exalbuminous 

 seeds, imbricated aestivation of the petals, and curious appendages 

 before each petal. These are explained, and the plan of the flower 

 shown, on p. 253 (Fig. 304, 305). In the ovary, also, the four 

 short stigmas are situated opposite the four parietal placentae. 

 The genus has been placed in Saxifragacese on account of its 

 slightly perigynous stamens, &c., and in Hypericaceae on account 

 of the sterile stamens in five sets, and the absence of albumen 

 in the seeds. 



724. Ord, CistaceSB (the Rock-Rose Family). Low shrubby plants 

 or herbs, with simple and entire leaves (at least the lower oppo- 

 site). Calyx of five persistent sepals, the three inner with a con- 

 volute aestivation ; the two outer small or sometimes wanting. Co- 

 rolla of five, or rarely three, regular petals, convolute in aestivation 

 in the direction contrary to that of the sepals, often crumpled, usu- 

 ally ephemeral, sometimes wanting, at least in a portion of the 

 flowers. Stamens few or numerous, distinct, with short innate 

 anthers. Fruit a one-celled capsule with parietal placentae, or im- 

 perfectly three to five-celled by dissepiments arising from the mid- 

 dle of the valves (dehiscence therefore loculicidal), and bearing 

 the placentae at or near the axis. Seeds few or numerous, ortho- 

 tropous (with few exceptions), with mealy albumen. Embryo 

 curved, or variously coiled or bent. Ex. Cistus, Helianthemum 

 (Fig. 546) : a small family ; the flowers often showy. No im- 



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