BROOM-RAPES, BALANOPHOREJ5, RAFFLESIACE^E. 



187 



the capitulum of a composite, by a whorl of imbricating scales, of which the lower 

 are shorter and broader, and the upper longer, narrower, and pointed at the apex. 

 These scales being stiff, somewhat shiny, and varying in colour from a waxen 

 yellow to orange or red — in the case of Langsdorffla Moritziana brown-red, — the 

 whole inflorescence has a vivid resemblance to certain immortelles, namely, the 

 large species of Helichrysum occurring at the Cape. The inflorescences bearing 

 male flowers are elongated and egg-shaped, those possessing only female flowers are 

 shorter and capitulate. The seeds dropped from the nut -like fruits, which are 

 pulpy internally, have no special integument. The embryo exhibits no trace of 



Fig. 38.— Langsdorffla hyp 



, from Central America. 



hit 1 ' ''-'- 



cotyledons or radicle, but consists of an undifferentiated group of cells which may 

 be likened to a tiny bulbil. 



Seeds of this kind germinate like those of Lathrcea, and upon meeting with 

 the root of a tree or shrub suitable for prey, develop into larger tubercles and have 

 a remarkable effect upon the substratum. The cortex of the host-root is destroyed 

 at the place of adhesion of the tubercle, and its wood is laid open, lacerated, and 

 unravelled. The woody bundles are diverted from their previous direction, ascend 

 towards the parasitic tubercle, which meantime has grown into a full-sized tuber, 

 and spread out like fans. The cells and vessels of the parasite penetrate between 

 the ascending wood-fibres, and this results in the formation of a zone at the place 

 of union of the parasite and root, where cells and vessels belonging to both inter- 

 lace, traverse, and join one another, coalescing completely in exactly the same way 

 as happens in the .case of the species of Tooth wort. A similar phenomenon occurs 

 also when one of the wavy stems of Langsdorffixt, comes into contact with a root 

 adapted to the purpose. The cortex of the root is demolished at the place of 



