STRUCTURAL BOTANY. 10 



and merely some obvious external circumstance noted. 

 An artificial system has no other aim than to serve as a 

 convenient means of reference, as a contrivance for den- 

 tif jing plants, and does not attempt to express fully their 

 points of resemblance. 



57. The best of all artificial systems is that of Lin- 

 nceus, Cliarles de Linne {Carolus Linnmus) was born 

 May 23d, 1707, in the hamlet Rashult, the province 

 Smoland, in Sweden. Ilis system consists of twenty- 

 four classes and a variable number of orders. It was 

 designed as a provisional substitute for the natural 

 classes and orders, which Linnseus would have established 

 himself, had such a thing been possible. In his day, when 

 the list of known genera embraced a comparatively very 

 small number of names, he divided the plants into two cardi- 

 nal series, Phcenogams and Cryptogams — a division which 

 is accepted by the authors of natural systems. But in de- 

 termining classes and orders, he proceeded differently. He 

 divided the Phmnogams into those with stamens and pis- 

 tils in the same flower, and those with these organs in 

 separate flowers. In the case of hermaphrodite flowers, 

 he examined whether their stamens are united with the 

 pistils or not; next, whether the stamens are united with 

 each other, and, finally, whether they were of equal or un- 

 equal length, if numbering 4 or 6. TJds systam is best 

 understood from a tabular view. 



I. Seeies : Stamens and Pistils Present. 



PH^:^OGAMIA. 



A. Stainens with the pistils in the same fi^wer : 



* Not united with the pistils, 

 ** nor with one another ; 

 *** of equal length, if 4 or 6. 



