108 JLINN/EAN ARTIFICIAL SYSTEM. 



The plants of this class might be confounded with those of the 

 fourth class tftrandria, which are also furnished with four stamens, 

 but in the last case they do not have any determinate inequality in 

 length, but are generally equal. (F. 177.) 



7. Should the plant you are wishing to analyze pro- 

 duce flowers furnished with six stamens, you must be 

 particular in assuring yourself that there are four long- 

 and two short ; and if there are, the fifteenth class or 

 tetradynamia is correct. (F. 188.) Flowers always of 

 four petals and cross-shaped. 



This class is only likely to he mistaken for the class hexandria ; 

 in the plants of which, there are also six stamens, but these are all 

 nearly equal in their height. (F. 179.) The orders of the fifteenth 

 class are established on the kind of seed-vessel, and being only two, 

 are easily comprehended. 



FOURTH DIVISION. 



8. If the plant ahout to be examined, does not 

 arrange in one of the first fifteen classes, you must 

 ascertain whether it does not belong to either of the 

 classes founded on a consideration of the union of the 

 stamens either with themselves or with the pistil. 



9. If the filaments are united with each other into 

 one set only, (F. 189.) the plant must belong to the six- 

 teenth class, or monadelphia ; if the filaments are united 

 into two sets, (F. 190.) to the class diadelphia ; or if they 

 are united into more than two, (F. 191.) then the class 

 polyadflphia would be the proper one. 



These three classes are very fairly distinguished from each other. 

 Nevertheless, it will be as well to observe, that both the classes 

 moncecia and dicecia have an order monadelphia, and that the former 



