DICOTYLEDONES : POLYPETAL^ : THALAMIFLORJ:. 



601 



C2 + 2, Aoz , G^- or (oc ), or rarely with triraeroas whorls : calyx 

 sepaloid, corolla petaloid : the numerous whorls of stamens alter- 

 nate : ovary of two lateral carpels or of more (Fig. 404 a), two- 

 or more-chambered : ovules numerous, attached to the more or 

 less infolded edges of the carpels : endosperm abundant, embryo 

 small. The sepals commonly fall off before the flower expands 

 (Fig. 404 A-). Plants with abundant milky latex. 



Papaver, the Poppy, has a many-chambered ovary ; the fruit is a porous 

 capsule (Fig. 342 D) : P. somniferum is cultivated for the sake of the oil con- 

 tained in the seeds, and for the latex obtained from its capsules, which, when 

 inspissated, constitutes opium : several species are British, such as P. Rhveas, 

 the Field Poppy; P. Argemone, the Pale or Long Prickly-headed Poppy; P. 

 hybridum, the Bound Prickly-headed Poppy ; P. dubium, the Long Smooth- 

 headed Poppy ; and Meconopsis cambrica, the Yellow Welsh Poppy. C helidormun 

 inaJHs, the Celandine, has 

 two carpels, a siliquose 

 fruit, and orange-coloured 

 milky latex. Glaucium, 

 the Horned Poppy, has a 

 siliquose fruit which is 

 generally spuriously bilo- 

 cular. Eschscholtzia call- 

 fornica is a cultivated 

 plant ; it has a hollow re 

 ceptacle, so that its flowers 

 are almost perigynous. 



Order 2. Fumaki- 

 kCEJE. Flowers isobi- 

 laterally symmetrical, 

 or zygomorphic with 

 lateral symmetry: 

 floral formula K2, (72 + 2, il2-l-2, G'^'. The three whorls of the 

 perianth alternate ; one of the outer petals (rarely both) is usually 

 furnished with a spur : in most genera there are three stamens on 

 each side, a central one, with a perfect anther (the stamen of the 

 outer whorl. Fig. 405 5 a), and two lateral stamens, each with only 

 half an anther (apparently the halves of the stamens of the inner 

 whorl; Fig. 405 Ba,a^. The fruit is siliquose and many-seeded, 

 or one-seeded and indehiscent. Herbaceous plants without milky 

 latex, sometimes climbing by means of their petioles which act as 

 tendrils (Adlumia, Fumaria). Seeds containing endosperm. 



Fig. 404. — Flower of Chelidanium majus (nat. size); 

 fc calyx ; ca outer, ci inner petals ; a stamens ; n stigma. 

 A Diagram of the flower of Chelidonium. a Many- 

 chambered ovary of Papaver. 



The flowers of Adlumia, Dicentra, and Hypecoum are isobilaterally symmet- 



