i8io 



A TEXTBOOK OF THEORETICAL BOTANY 



shrubs or herbs and many of them are parasitic. Leaves when present are 

 opposite but they may be reduced to scales. The floral parts are often 

 reduced, the ovary is inferior, the placentation axile and the ovules few in 

 number. The seeds have abundant endosperm and the embryo is straight. 

 As originally constituted the order contained some eight families, to three of 

 which we shall refer briefly, the Loranthaceae, Balanophoraceae and 

 Santalaceae. 



The Loranthaceae are a family of parasitic shrubs with green leaves, 

 but deriving the greater part of their food as parasites. There are thirty 

 genera and about 520 species, occurring in temperate and tropical regions. 





Fig. 



1706. — Viscwn alhiiiii. Mistletoe. Habit of plant 

 growing on the branch of an apple tree. 



The only British genus is Visciim\ V. album (Fig. 1706) is the Mistletoe. 

 The plants are attached to their hosts by suckers which have been variously 

 interpreted, but are generally thought to be adventitious roots greatly 

 modified as organs of absorption. A few species root in the ground but 



