666 



SYSTEMATIC BOTANY. 



esculent. Some species of Dioscorea are very acrid even when boiled, and 

 cannot therefore be used for food. 



Tamus. — T. communis. Common Black Bryony, has a large fleshy root 

 which when fresh possesses considerable acridity. It is sometimes used as 

 a topical application to bruised parts to remove the marks. Taken inter- 

 nally, it acts as a diuretic, and also, it is said, as an emetic and cathartic. 

 The young shoots of this species, and those of T. cretica, when thoroughly 

 boiled, so that their acridity is desti'oyed, have been eaten like asparagus. 



Testudinaria elephantipes, a native of the Cape of Good Hope, has a very 

 peculiar tuberous stem, hence it has been called Elephant's foot or Tortoise 

 plant ; the inner part of this is very mealy, and is used for food by the 

 Hottentots. 



Natural Order 243. Smilace.^. — The Sarsaparilla Order {fig. 

 1029). — Character. — Herbs or shrubs, more or less climbing 

 {fig. 1029). Leaves petiolate {fig. 1029), net-veined, articulated. 



Fig. 1029. 



Fig. 1029. A portion of a branch, with leaves and fruit of the Smilax papyracea. 



Flowers regular, unisexual and dioecious, or hermaphrodite. 

 Perianth inferior, 6-parted, with all its divisions alike. Stamens 

 6, perigynous or rarely hypogynous; anthers introrse. Ovary 

 superior, 3-celled ; stigmas 3. Fruit a berry {fig. 1029), few or 

 many-seeded. Seeds with a minute embryo, albuminous. 



Distribution, <^'c. — The species are scattered over various parts 

 of the world, both in tropical and temperate climates : they 

 are, however, most abundant in tropical America. Examples of 

 the Genera: — Smilax, Eipogonum. There are probably about 

 120 species, but some botanists make the number considerably 

 more. 



Properties and Uses. — The plants of this order generally 

 possess alterative properties. 



Ripogonum parviflorum has similar properties to Sarsaparilla. (See 

 Smilax.) It is a native of New Zealand, where it is much used as a remedial 

 agent. 



Smilax. — The roots of several species or varieties of Smilax constitute the 

 Sarsaparilla of the materia medica, which is commonly regarded, and in our 



