528 



MANUAL OF POISONOUS PLANTS 



itching. The plant is used for the expulsion of intestinal worms, the hairs 

 being mixed with honey and molasses. The young pods are used as food. 

 The Calabar or ordeal Bean (Physostigma venenosum) is a climbing peren- 

 nial plant resembling the scarlet runner and is native to tropical western Africa. 

 It was formerly used by the natives to produce poisoning and is also an anti- 

 dote against strychnin poisoning. The seeds contain several poisons, among 

 them the alkaloids physostigmin C 15 H 01 N 3 O 2 which contracts the pupil of the 

 eye, calabarin a tetanizing principle, and eseridin C 15 H 03 N 3 O a purgative. 

 The wood of Araroba (Andira araroba) is very bitter and is used in oint- 

 ments. Balsam of Tolu (Myroxylon toluiferum}, a native of Veneuzela and 

 New Granada, is used as an ingredient in lozenges and contains a volatile oil 

 tolene C 10 H 16 . 



Logwood (Haematoxylon campechianum} is a spreading tree, native to 

 Central America and Honduras, the bark of which is used for dyeing and 

 staining, also for domestic purposes, such as in chronic diarrhoea, and contains 

 heamatoxylin C 16 H 14 O G and heamatein C 16 H 14 O 6 . Senna leaves are derived 

 from the leaves of Cassia (C. acutifolia and C. angustifolia}, the former being 

 found in Nubia and the latter in southern Arobia and India. Senna leaves are 

 used in medicine as a purgative and contain cathartic acid, chrysophan and two 

 bitter principles sennacrol and sennapicrin. Several of our native species of Cas- 



Fig. 287. European Licorice (Glycyrrhisa giabra). 

 (After Faguet). 



