EXOGENJE MONOCHLAMYDEJE. 



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an involucre, monoecious or dioecious. Calyx lobed, some- 

 times wanting. Corolla consisting of petals, or scales, or 

 absent. Stamens definite or indefinite. Ovary superior, 

 2- or 3-celled ; ovules solitary or twin; suspended ; styles 

 equal in number to the cells; stigma compound or single. 

 Fruit generally consisting of 3 dehiscent cells, separating 

 with elasticity from their common axis; embryo in fleshy 

 albumen. 



USES. Castor-oil is obtained from the seeds of Ricinus 

 communis ; Tiglium-oil from that of Croton Tiglium ; and 

 a similar purgative quality seems to be general in the seeds 

 of the order. Cascarilla is the bark of Croton Eleutheria ; 

 and the same aromatic principle occurs in many species. 

 Many are deadly poisons, as Manchineel, Hysenanche, Sapium 

 aucuparium, Sec. The drastic drug Euphorbium flows from 

 the stem of some succulent Euphorbias in North Africa. 

 Boxwood, so useful to wood engravers, is the timber of 

 Buxus sempervirens. Cassava, or Mandioc, or Tapioca, a 

 nutritious substance consisting of starch, is obtained from 

 the stem of Jatropha Manihot, a poisonous plant ; but it is 

 purified by washing and torrefaction. 



TYPICAL GENERA. Buxus, Andrachne, Cluytia. 



1. The involucre of a Euphorbia, containing monandrous male florets, surrounding 

 a long-stalked female. 2. 3. 4. Male florets of different species, with the articulation 

 that separates the filament from the pedicel. 5. A carpel separate. 6. A vertical 

 section of an ovary. 7. A vertical section of a ripe seed, showing the central column 

 and an embryo in the midst of albumen. 



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