274 COMMON WEEDS 



sometimes pinkish, and is practically devoid of chloro- 

 phyll. The flowers appear in April and May ; they 

 are dull purple in colour, and are arranged in un- 

 branched scaly racemes, which are curved downwards 

 at the tip when young. The corolla is two-lipped and 

 open. 



LORANTHACE/E 



Mistletoe (Viscum album L.) This familiar ever- 

 green parasite is capable of attacking a great variety of 

 trees, but is perhaps most abundant on poplars and on 

 apple-trees in orchards, where it does a considerable 

 amount of damage. 



The stems are round, dichotomously branched or 

 " forked," and yellowish-green, like the opposite fleshy, 

 obovate-lanceolate leaves. The plant is dioecious, the 

 small four-petalled male flowers being on one individual, 

 and the female flowers on another. 



The latter have inferior one-celled ovaries, which 

 develop into round, white, semi-transparent berries, the 

 contents of which are extremely viscid. Flowering 

 takes place in March and April, and the berries are 

 ripe about November and December, at which time they 

 are distributed by thrushes and other birds ; the seeds 

 are deposited in excreta or rubbed by the beaks of the 

 birds on branches of trees. 



The seeds begin to germinate about April or May, 

 when they send out a root which immediately curves 

 towards and penetrates the bark, dissolving its way by 

 means of enzymes down to the young wood. In a 

 year or two the primary root produces green lateral 

 roots, which grow out from it at right angles and 

 extend along the branch mostly in the bast. From 

 the lower side of these lateral rhizome-like rootlets short 

 roots or " sinkers " are pushed out into the wood, from 



