IO2 Chapters in Modern Botany CHAP. 



three hundred species of mistleto-like plants included in 

 the order Loranthaceae, while the genus Henslowia plants 

 of similar habit found in Southern Asia and in the Indian 

 Archipelago belongs to the order Santalacea?. 



It is interesting to notice that some of these mistleto-like 

 plants are sometimes parasitic on one another. Thus our 

 mistleto may grow on Loranthus europaus, or one species 

 of Viscum or of Loranthus may grow on another ; indeed 

 the common mistleto has been noticed as is natural and 

 perhaps common enough thus sprouting upon itself. 



Dodder. The dodders (Cuscuta) are parasites on such 

 plants as clover, flax, nettles, and hops. It is on the two 

 last that the commonest European species (C. europcza) 

 is usually found. In many ways it differs from the mistleto; 

 thus the seed almost always germinates on the ground, and 

 the adult plant is practically destitute of chlorophyll and 

 leaves. 



Let us follow the life-history of the common dodder. 

 Like most of the other species, it is an annual, dying away 

 in autumn. Before that, however, the seeds have burst 

 explosively from the seed-boxes, and have been swept hither 

 and thither by the wind. All through the winter they lie 

 dormant on the ground, sheltered in many cases by decay- 

 ing leaves, which supply a suitable bed for germination. 

 This does not take place till comparatively late in the 

 following year, not before the nettles and hops have acquired 

 some strength of stem, a delay which is obviously of 

 advantage to the dodder. 



Out of the seed there comes a little club-shaped root 

 which seeks the soil, but the young stem remains surrounded 

 by the seed-husks and the store of nutriment which these 

 enclose. It grows thin as a thread, and somewhat spirally 

 at the expense of the seed-store. This is soon exhausted 

 and growth practically stops, but the thin stem still circum- 



