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BRITISH FLOWERING PLANTS 



woody root, parasitic on the roots of other plants, 

 and throwing out recumbent shoots round it several 

 inches long. It is confined in Britain to chalky 

 districts. The small greenish yellow flowers, with 

 white petals, have the perianth deeply cleft, and 

 united to the ovary ; 4 or 5 stamens opposite the 

 petals ; and a single style. Ovary with 1 cell and 

 2 pendent ovules. 



Order LXXX. Aristolodiiacece (2 genera) 

 This is another small family, chiefly tropical and 

 subtropical, represented in Britain by 2 species 

 only. They have tubular flowers, with an oblique 

 lobe, the perianth united with the ovary, and 

 several stamens placed on the ovary, which is 

 formed of several cells containing many seeds. 



Birthwort — A ristolochia Clematitis. 



(Plate LXXXVI) 



This is a South European plant, naturalised in 

 various places in Central Europe, in hedges, on 

 rubbish-heaps, especially about vineyards ; and in 



England chiefly about ruins. It has an upright 

 smooth stem, nearly 2 ft. in height, large smooth 

 heart-shaped leaves, and yellow flowers in the axils 

 of the leaves. The root is sometimes used in 

 medicine. 



Asarabacca — Asarum europium 



(Plate LXXXVII) 



This is a widely-distributed but not very common 

 plant, found under hedges and in damp woods. 

 The large leaves grow two together from the root- 

 stem, and are entire, leathery, shining above, and 

 of a paler green below, reticulated with veins ; the 

 borders are entire. The perianth is greenish red 

 outside, and dark purple inside. It is trifid, and 

 attached to the ovary ; and has, like the root, a 

 sharp penetrating odour, due to an essential oil 

 which it contains. 



Order LXXX I. Empetracece (1 genus) 



There is only one British species of this Order, 

 the Crowberry (Empetmm nigrum), which is found 



