SPERMATOPHYTA— ARACEAE— AROIDS 



371 



Many of the plants, as the skunk cabbage, Symplocarpus foetidus, possess 

 acrid and noxious qualities. This is a native herb which is acrid and has a 

 disagreeable odor. The fleshy spadix of Monstera delidosa of the Mexican 



Fig. 158. Common European Arum, Cuckoo-pint, or Wake-robin 

 {Arum wacuiatum). Leaf; spadix; longitudinal section of ovary; germina- 

 tion; longitudinal section of seed; embryo. (After Faguet.) 



Cordilleras is edible. The vegetable calomel (Acorus Calamus) is used in 

 medicine and contains the bitter principle acorin and an alkaloid. The sweet 

 calomel is poisonous, under some conditions, causing disturbed digestion, and, 

 in severe cases, gastro-enteritis, persistent constipation, followed by diarrhoea 

 and passage of blood in the feces. 



The Calla palustris, a marsh plant, has acrid properties and is used in 

 Lapland with bread. The bulbs of Amorphophallus are rich in starch and are 

 edible. The Richardia africana is frequently cultivated and used as food, a 

 starch being also made from it. The poisonous substances contained in it are 

 removed on roasting and boiling. In some of the fruits of aroids, \ike Arum 

 italicum, saponin has been found, also needle-like crystals of oxalate of lime. 

 A. maculatum is poisonous and causes severe dermatitis, paralysis, and, in the 



