522 BOTANY 



Geographical Distribution. — The Papaveraceae constitute a small family 

 restricted almost entirely to the North Temperate Zone. 



Poisonous. — Papaver somniferum (Opium Poppy) contains in all its organs 

 a poisonous, milky latex. It is an annual herb with glabrous, somewhat glaucous 

 stems and leaves, and is cultivated for the sake of the oil accumulated in the 

 seeds, also for the latex obtained from the unripe capsules ; the latex, on 

 hardening, constitutes opium. The leaves are sessile, irregularly incised and 

 toothed. The flowers are solitary, borne upon a long stalk with bristly hairs 

 (Fig. 483). They are nodding while in the bud, but become afterwards erect ; 

 they have a fugacious calyx and white or violet petals with crumpled aestivation. 

 The fruit is a broad capsule more than 6 cm. in length, enclosing numerous 

 reniform seeds of a white or violet colour. Other species of Papaveraceae are 

 also toxic, but in a less degree. 



Officinal. — Papaver somniferum, yielding Fructus Papaveris immaturi, 

 Semen Papaveris, and Opium. 



Family Resedaceae. — Flowers zygomorphic, perianth consisting of two- toeight- 

 merous whorls ; petals deeply fringed. Sexual organs usually borne upon a 

 gynophore ; stamens three to forty ; carpels two to six, free or united, forming 

 a unilocular ovary open at the apex. Herbaceous or shrubby plants, chiefly 

 Mediterranean, with small flowers, e.g. Reseda luteola (Dyer's Weed), B. lutea 

 (Base Rocket), B. odorata (Mignonette). 



There is considerable uncertainty as regards the systematic position of the 

 plants included in the family Besedaceae ; they are considered to be allied to the 

 Capparidaceae. 



Order 7. Cistiflorae 



Flowers hypogynous, generally actinomorphic and hermaphrodite. 

 Calyx imbricated in the bud ; the whorl of the perianth and androecium 

 typically pentamerous, but the androecium often polymerous by the 

 division of the stamens ; gynaecium usually three- to five-merous, and 

 syncarpous ; ovary unilocular, with parietal placenta?, less frequently 

 multilocular ; ovules for the most part anatropous ; embryo usually 

 straight. 



The Cistiflorae form a somewhat artificial order ; they comprise 

 families which, in most cases, have been previously assigned to different 

 systematic positions. The flowers exhibit the regular Dicotyledonous 

 type or a modification of it, resulting from the division or suppression 

 of some of their parts, but without at the same time showing any uni- 

 formly occurring characteristics of general significance. There is more- 

 over in this order no predominant type about which the less distinctive 

 forms may be grouped. Many of the Cistiflorae show an affinity to the 

 Besedaceae, and through them to the Ehoeadinae ; others, in particular 

 the Ternstroemiaceae, to the Columniferae ; and some are allied to the 

 Passiflorinae. 



Family Cistaeeae. — Flowers actinomorphic, with numerous 

 stamens ; gynoecium three- to five-merous ; ovary usually unilocular, 

 with parietal placentae ; style simple ; ovule atropous ; fruit a 

 capsule ; seeds with endosperm ; embryo curved. 



