154 SYSTEM OF LINN^US. 



the sixteenth, seventeenth, and eighteenth, relationships 

 of connection of the filaments of the stamens ; in the 

 nineteenth, of the anthers ; in the twentieth, of the sta- 

 mens and pistils ; in the twenty-first, twenty-second, and 

 twenty-third, the sexual relations of the individuals in 

 regard to uni- sexuality and hermaphroditism, are the 

 governing principles ; and in the twenty-fourth and last, 

 the apparent want of analogy in the reproductive struc- 

 tures of certain plants, to those upon which the fore- 

 going classes are founded. 



8. The next most general divisions of the system are 

 the orders which are formed upon the number of styles 

 or stigmas, as far as relates to the first thirteen classes, 

 and are named 



Monogynia, plants which have...,. 1 style. 



Digynia 2 styles. 



Trigynia 3 styles. 



And so to Polygnia. , .... more than 12 styles. 



The whole of the orders do not cccur in each class ; 

 sometimes only two or three, as Monogynia, Digynia, 

 and Tetragynia ; in the fourth class Tetrandria. 



9. In the 14th class, Didynamia, there are two orders 

 which are made to depend upon the nature of the ova- 

 rium ; or as Linnaeus considered them, as to whether the 

 plants had naked or covered seeds. The first order is 

 Gymriospermia, in which the ovarium is 4-lobed, or 

 with naked seeds, ace .jrding to the old erroneous notions ; 

 and the second is Angiospermia, in which the ovarium 

 is not lobed, or with covered seeds. 



10. In the 15th class, Tetr -adynamia, there are two 

 orders formed upon the nature of the fruit. The first 

 is Siliculosa, in which the plants have a short pod, or 

 one broader than it is long ; the other, Siliquosa, in 

 which the pods are much longer than they are broad. 



11. In the 16th, 17th, and 18th classes, Monadel- 

 phia, Diadelphia, and Polyadelphi'a, the orders are formed 

 upon the number of the stamens, and receive the same 



