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A TEXTBOOK OF THEORETICAL BOTANY 



The Hypecoideae is a small sub-family containing two genera, Hypecoum 

 and Pteridophyllum. The flowers are dimerous and actinomorphic. The 

 stamens are four in number and developed opposite the petals. The fruit 

 is a long pod or lomentum derived from a bicarpellary gynoecium. Later in 

 life it becomes divided up by transverse septa into one-seeded portions. The 

 plants are mostly perennial herbs with pinnately divided leaves and are 

 devoid of any laticiferous system. Hypecoum contains some twelve species 

 which range through Europe to central Asia and China. Pteridophyllum is 

 represented by a single Japanese species. 



In H. prociimbens the pollen is shed in the bud into pockets on the inner 

 surface of the inner petals, which close up before the stigma develops. The 

 stigma only opens when it has grown above the level of the pollen pockets. 

 When an insect visits the flower, the pockets open and dust it all over with 

 pollen. 



The members of the Fumarioideae are distinguished by the marked 

 difference in appearance of the two whorls of petals; also by the spurs which 

 are developed at the base of one or two of the inner petals and by the two 

 tripartite stamens. There is no laticiferous system but oil-containing sacs 

 may be present. The plants are mostly small herbs, though some climb 

 with the aid of their thin, slender stems and much divided leaves. Unlike 

 most of the Papaveroideae, the flowers are small and are borne in terminal 

 racemes and they are insect pollinated. In Dicentra (Fig. 1497), Corydalis 



Fig. 1497. — Dicentra formosa. Flowering 

 shoot. 



and Fumaria the flowers are interesting as examples of a rare type of 

 zygomorphy in which the plane of symmetry is transverse and vertical to 

 the central axis. In Corydalis the fruit is a many-seeded, bivalved capsule, 

 while in Fumaria it is an indehiscent, one-seeded nut. Many species of 



