620 



BOTANY 



PART II 



Orders 5-7 are isolated, and also have no evident connection with 

 one another. 



Order 5. Loranthiflorae 



Family 1. Santalaceae. Green plants growing in the soil and partially 

 parasitic on the roots of other plants from which their haustoria obtain nutrient 

 materials. In Britain, Thesium. 



FIG. 616. Vlxcum album. With flowers and fruits. ( nat. size.) 



OFFICIAL. Santalum album, the wood of which when distilled yields OLEUM 

 SANTALI. The wood is also of economic value. 



Family 2. Loranthaceae. Leafy semi-parasitic shrubs, living on the branches 

 of trees. They are most abundant in the tropics, and, for instance in South 

 America, add to the beauty of the forest by their brightly coloured flowers. 



Loranthus europaeus, on Oaks in Europe. In Britain Viscum album (Fig. 636), 

 the Mistletoe, occurs as an evergreen parasite on a number of trees. It has opposite, 

 obovate leaves. Stem swollen at the nodes. The white berries are distributed by 

 birds. The sucker, without a root-cap, emerging from the seed penetrates the 

 cortex of the host to the wood, into which it cannot grow. Its tip is embedded in 

 the new wood formed by the cambium of the host. Further growth in length 

 of the sucker is eifected by a zone corresponding in position to the cambium 

 of the host. 



