NATURAL ORDERS. 89 



10. Plants which have a milky juice, unless compound, are 

 poisonous ; as Dog's-bane, Jlpocymun ; Milkweed, Asclefiias. 



11. Plants having any appendage to the calyx or corolla, and 8 

 or more stamens, generally poisonous ; as Columbine, Jlquilegia ; 

 Monk's-hood. See Eaton's Manual, page 11. 



We have now gone through with what is necessary to become 

 acquainted with genera and species, in a knowledge of which Bo- 

 tanical science principally consists. The next chapter contains 

 some observations on Natural Orders, and the general relations of 

 plants, of which the student cannot possibly form a very definite 

 conception, until he is more or less acquainted with genera. It is 

 well enough however for him to read them, but he must not be 

 dissatisfied with himself or discouraged if he does not at once un- 

 derstand them in every particular. 



CHAP. III. 



NATURAL ORDERS. 



A NATURAL ORDER consists of a number of 

 genera, which are allied to each other by botanical af- 

 finities ; which have an evident agreement with each 

 other in some of their most essential parts. 



In a Natural Method the Artificial Divisions, Classes 

 and Orders are set aside and the vegetable kingdom 

 stands divided, first into those primary divisions, 

 NATURAL ORDERS, which nature has marked out. 

 These are divided, in the next place, as artificial classes 

 and orders are, into genera ; and the genera into species. 



The Artificial arrangement of the vegetable kingdom into Clases 

 and Orders, for the purpose of determining the name and history 

 of an unknown plant in an easy and' direct manner, was thought 

 by Linnseus to be a matter of necessity ; because Natural Orders 

 cannot be stamped with a single definite character by which the 

 individuals of each might be readily knovvn But still he consid- 

 ered a Natural method as the perfection of Botanical science. See 

 page 64. 



Take a fruit garden for an example of a natural or- 

 der. The Cherry and Plum are two species of the 

 genus Prunus ; Peach and Flowering Almond, two 



8* 



