396 



DICOTYLEDONES. 



393 B, 395, 396). The fruit is a many-seeded siliqua-like capsule. 

 A peculiarity of the flower is that the plane of symmetry passes transversely 

 through the flowers, whilst in nearly all other zygomorphic flowers it lies in 

 the median line. Moreover, the flower is turned, so that the plane of symmetry 

 ultimately becomes nearly vertical, and the spur is directed backwards. Many 

 species have subterranean tubers; in these the embryo germinates with one. 



FiG. 393. Diagram of Dtcenfro (A), Corydalis (S), and Hypecoum (C). 



coiyltdon, which is lanceolate 1 and resembles a foliage-leaf. The tuber is in 

 some the swollen hypocotyl (C. card), in others a swollen root (C. fabacea, 

 etc.), which grows down through the precisely similar swollen root of the 

 mother-plant. The sub-genus Cerat.ocapnos has dimorphic fruits (nuts and 

 capsules) in the same raceme. Fumaria differs from Corydalis only by 

 its almost drupaceous, one-seeded nut (Fig. 395). 



THE STRUCTURE OP THE FLOWER. Hijpecoum among the Papaveraceee is the 

 connecting link with the Fumariacese. The diagram (Fig. 393 C) corresponds 

 both in number and in the relative position of its members with that of most 

 of the other Papaveraceae (Fig. 391), except that there are only four stamens 

 (with extrorse anthers). In Dicentra (Fig. 393 A), the two central (uppermost) 

 stamens are absent, but each of the two lateral ones are divided into three 

 filaments, of which the central one bears a four-locular anther, and each of the 



Fie. 394. THcentra spectdbilis: A flower () ; B the same, after removal of half of one 

 outer petal; the cap, formed by the inner petals, is moved away from the anthers and 

 stigma; the insect does this with the lower side of its abdomen, and thus rubs the stigrna 

 on the hairs of its ventral surface; the dotted line at e indicates the direction of the 

 proboscis ; C androecium and gynoeceum ; D stigma. 



