THE MISTLETOE FAMILY 139 



leaves, or leaves considerably reduced in size. Hence it is 

 that many parasitic plants have a very much reduced stem 

 structure and leaf area. In some of them little more than a 

 flower is developed, cf. Cuscuta, Cassytha, Dactylanthus. 

 Since parasites do not grov^ like other plants in the soil, but 

 send out processes which penetrate into the woody tissues of 

 their hosts, their method of germination is often quite 

 abnormal. Very frequently also the seed leaves are poorly 

 developed or altogether wanting, and the parts of the embryo 

 are but little differentiated. (Contrast Avicennia.) 



New Zealand is very rich as compared with Great Britain 

 in woody parasites. In England there is only one such plant, 

 the Mistletoe {Viscum album). It grows commonly on soft- 

 wooded trees such as the poplar, silver fir, and apple. It 

 rarely attacks the oak, and when it did so it was an object of 

 worship to the Druids of early Britain. 



Key to the Oenera. 



1. Leaves 0., branches jointed, flattened. Viscuin, p. 144. 

 Leaves present. 2 



2. Leaves opposite. Flowers hermaphrodite. Loranthus, p. 139. 

 Leaves opposite and alternate, flowers dicecious. Tupeia, p. 144. 



Genus Lorcuithus. 



An extremely interesting genus of about 200 species, all the members of 

 which are semi-parasitic shrubs. Flowers solitary or in racemes. Calyx cup- 

 shaped, more or less toothed. Corolla tubular, petals 4, free or united below. 

 Stamens 4, inserted on the petals. Style slender, deciduous. 6 sp. 



The genus Loranthus is widely distributed throughout 

 tropical and sub-tropical regions, and some of the species 

 produce handsome and brilliant flowers in great abundance. 

 The finest of the New Zealand forms is L. tetrapetalus. It is 

 found most frequently upon Nothofagus Solandri. No finer 

 floral display can be seen in New Zealand than a gloomy forest 

 of Fagus trees lit up by immense masses of scarlet Loranthus 

 flowers, glowing like jewels among the dark green leaves of 

 the beech. It is seen, perhaps, at its best when one rows up 



