PARASITIC PLANTS 



345 



the ground until it reaches the root of some herb or shrub. It then 

 gives off suckers which penetrate into the root, and, with the aid 

 of the organic food thus obtained, forms a tuberous swelhng on its 

 surface. Flowering stems are afterwards produced, and these, 

 rising above the soU, bear terminal spikes of hpped flowers, followed 

 by capsules containing many seeds. 



There are several British 

 species of this genus (Orobanche), 

 and their flowering stems, which 

 are usually unbranched, pro- 

 duce scale-hke leaves of the 

 same colour as themselves. 

 Each flower of the spike is in 

 the axil of a bract resembhng 

 the scales of the lower part of 

 the stem ; and in some species 

 there is a pair of smaller bracts 

 close to the base of the calyx. 

 The corolla is either tulmlar or 

 bell-shaped, and more or less 

 distinctly lipped. Each flower 

 has four stamens, arranged in 

 pairs, and a two-lobed stigma. 

 The following outline of leading 

 featm*es will serve for the 

 identification of the common 

 Broomrapes : — 



1. The Great Broomrape 

 (0. Rapum). — A plant from 

 twelve to eighteen inches high, 

 of a pale yellow colour at first, 

 but afterwards turning to a dull 



purple brown. Stem thick, especially below, and unbranched. 

 Scales lanceolate. Flowers sessile, whitish, with only one bract, 

 forming a spike from six to nine inches long. This species is 

 moderately common, and is parasitic on the roots of Furze and 

 Broom. Time of flowering — May to July. 



2. The Clove Broomrape {0. caryo'phyllacea). — Very similar 

 to the Great Broomrape in colour, but usually smaller, and easily 

 distinguished by the sweet clove-like scent of its flowers. Spike 

 not so dense as in the last'species, and the corolla tube not so broad. 



THE Great Broomrape. 



