THE MOXOCOTYLEDOXES 



201 I 



The flowers (Fig. 1948) are small or even minute, hermaphrodite and 

 all alike, or monoecious, arranged in a cylindrical spike called the spadix. 

 The males are borne in the upper part of the spadix, with the female tiowers 



Fig. 1948. — Floral diagram of 

 Acorns calamus. Araceae. 



below. This spadix is always surrounded by a large bract, the spathe, 

 which may be green or brightly coloured. 



The perianth, which is present in hermaphrodite flowers, consists of 

 four to six connate segments formed into a truncated cup. 



The androecium consists of one to six hypogynous stamens, frequently 

 coherent into a synandrium. The anthers open by pores or slits and may 

 be free or united into a single group. Staminodes may be present in female 

 flowers. 



The gynoecium consists of one or more carpels which may form a 

 unilocular or multilocular ovary, sometimes without a style. The ovules 

 may be one or many and their point of attachment is variable. 



The fruit is a berry containing one or many seeds. 



The seeds are mostly endospermic, with a straight embryo lying in the 

 middle of the endosperm. In the absence of endosperm the embryo is 

 curved. 



The family contains slightly over 100 genera and about 1,900 species. 

 Though widely distributed in temperate regions its centre of distribution 

 appears to be the tropics of the Old World. Many are climbers or epiphytes, 

 the latter forming an important constituent of the vegetation of the tropical 

 rain forests. 



Morphologicallv the family is interesting, especially the roots, which are 

 all adventitious. Most of the climbing and epiphytic species develop both 

 absorptive roots which grow downwards towards the soil and clasping 

 roots which are sensitive to light but not to gravity and by them the plants 

 become attached to their supports. Other plants may begin life as epiphytes 

 by the germination of the seed on a branch. In this case the seedling may 

 first produce clasping roots to attach it to the branch and then unbranched 

 aerial roots which grow downwards, but may never reach the ground and 

 hang freely in the air. Many of these aerial roots develop a velamen similar 



