534 



PART IV. CLASSIFICATION. 



or zygomorphic with lateral symmetry : floral formula A"2, C'2 + 2, 

 A2 + 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. 346 B a), and 

 two lateral stamens, each with only half an anther (apparently the 

 halves of the stamens of the inner whorl ; Fig. 346 B a t 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. 



The flowers of Adlumia, Dicentra, and Hypecoum are isobilateralJy 

 symmetrical. ])icentra spectabilis is a favourite ornamental plant; both 

 the outer petals are spurred, the two inner petals are hollowed at their 

 apices, so that they completely enclose the anthers. In Hypecoum the 

 petals are not spurred, and there are four stamens, two lateral forming 

 the outer whorl, and two antero-posterior forming the inner whorl : fruit 

 usually indehiscent. In Corydalis and Fumaria only one of the outer 



FIG. 346<-^l Flower of Dicentra spectabilis : one of the outnr petals is removed : s pedicel ; 

 ca the outer, ci the inner petals ; / stamens. B The three stamens of one side, seen from 

 within : /filaments ; a the middle complete anther ; a, a, the lateral half-anthers. C Flower- 

 bud, with the sepals, which soon fall off, still adhering (fc)i (nat. size). Diagram of Fumi- 

 tory. 



petals is spurred, and consequently the flower is irregular and laterally 

 zygomorphic (p. 455). In Corydalis the fruit is atwo-valved capsule with 

 numerous parietal seeds : some species, e.g. C. cava and solida, have a 

 tuberous rootstock ; others, as C. lutea and aurea, have rhizomes. Fumaria 

 officinalis, and others (Fumitories) are common in fields ; the ovaries 

 contain but few ovules, and of these only one ripens to a seed ; fruit 

 globose, indehiscent. 



Order 3. CRUCIFER^:. Flowers regular, isobilateral : floral for- 

 mula K2 + 2, C x 4, A2 + 2 2 , 6P. The four petals form a whorl, alter- 



