SECT. II PHANEROGAMIA 



Aldrovanda vesiculosa is a European water-plant that also occurs in India and 

 Australia. 



(For further iufornuition on insectivorous plants cf. p. 228.) 



Family 13. Aristolochiaceae. — The Aristolochiaceae may be associated with 

 the Polycarpicae on account of the numerical relations of the floral organs in spite 

 of their inferior ovary ; their flowers are often zygomorjjhic and they thus present 

 analogies with the Ranunculaceae. Herbs and twining shrubs with simple cordate 

 leaves. Flowers with a simple, gamophyllous perianth. Androeceum and gynaeceum 

 united to form a gynostemium. P3, A 6 + 6 G(6) ovary inferior, septate. Fruit 

 a capsule. Distributed over the whole earth, but mainly in South America. 



Asaram Europeum with actinomorphic flowers occurs in Britain. Aristolochia 

 clcmatiiis (Fig. 575) with zygomorphic, protogynous flowers (for pollination 

 cf. p. 501) are erect herbs with large alternate leaves. Numerous solitary flowers 

 in the leaf-axils. 



Family 14. Rafflesiaceae (^'). — Parasites with vegetative organs reduced to 

 hausteria ; without chloroiihyll. Flowers often very large (Ilafflesia). Tropical. 

 Hafflesia Arnoldi (Sumatra) has the largest known flowers, attaining a diameter 

 of 1 m. 



Order 12. Rhoeadinae 



Herbs, or more rarely shrubs, with alternate, exstipulate leaves. 

 Flowers hermaphrodite, cyclic ; whorls usually bimerous. Ovary 

 superior, unilocular. Placentas on the united margins of the carpels, 

 projecting more or less into the cavity. Stigmas commisural, i.e. 

 situated immediately over the sutures. Dehiscence of the fruit by 

 separation of the middle portions of the carpels from the persistent 

 placentas. 



Family 1. Papaveraeeae. — Herbs with milky juice. Leaves usually 

 pinnately lobed. Flowers actinomorphic. Floral formula, K 2, C 2 -i- 2, 

 A X G (2) or go. Seeds with abundant endosperm. 



The number of the stamens, and usually their position, is indefinite. 

 In the genera Chelidonium, Glaucium, Escholtzia, there are two carpels ; 

 in Papaver, Argemone, and Meconojjsis the number is greater (15-16) 

 (Fig. 576). 



Mainly in the northern hemisphere outside the tropics. 



Important Native Geneiia. — Chelidonium majus, Celandine, has yellow latex 

 and a bicarpellary ovary. A number of species of Esclioltzia, Aryemone, and 

 Papaver are cultivated as ornamental plants. Papaccr Rltocas, the Poppy (Fig. 

 577), is a common weed in corn-tields or dry meadows. The leaves are narrow and 

 pinnately divided. .JThe whole plant is covered with coarse, bristly hairs. The 

 bent position of the flower-bud is characteristic of many Papaveraeeae. Ultimately 

 the flower becomes erect as it opens ; the two sepals forming the calyx are thrown 

 off, and the four, large, wrinkled petals, forming the corolla, expand. Papaver 

 somnifcruin, whieli is of oriental origin, has abundant white latex. The plant has 

 a glaucous bloom and, except on the flower-stalks, which bear a few bristly hairs, 

 is glabrous. Leaves sessile, margin irregularly serrate or lobed. Petals violet or 

 white with a dark patch at the base. Ovary unilocular, incompletely septate by 



