164 



TAXONOMY. 



or absence of the corolla, the consistency of the fruit, and the adhesion or not 

 of the ovary with the receptacular tube. The problem of a classification by 

 natural affinities had thus been long propounded ; it was solved by A. L. de 

 Jussieu, who discovered the grand principle of the relative value of characters. In a 

 Memoir on Ranunculacece, he enunciated and developed the relative and subordinate 

 importance of the different organs of a plant ; this was followed by his great work on 

 the Families and Genera of the Vegetable Kingdom ; and the clear principle of the 

 subordination of characters, which had guided him in his labours, thereupon threw 

 great light on all other branches of Natural History. 



TABLE OF THE NATURAL METHOD OF A. L. DE JUSSIEU. 



ACOTYLEDONS 



MONOCOTYLEDONS 



Apetilous 

 flower. 



Monopetalous J 

 flower. 



( Stamens inserted on the receptacle 

 ,, calyx 



ovary 



ovary 



calyx 



,, receptacle 



Staniiniferouscorolla inserted on the receptacle 

 .. ... .. cui \ x 



Stnnu-ns inserted on the ovary 



receptacle 



calyx 



Male and female flowers on different plants 



Polypetalous 

 flower. 



Classes 



1 ACOTYLEDONIA . 



2 MONO-HYPOGYNIA 



3 MoNO-PERIGYNIA 



4 MoN'O-EPIGYNIA . 



5 EPISTAMINIA 



G PERISTAMINIA 



7 HYPOSTAMINIA . 



8 HYPOCOROLUA . 



9 PERICOROLLTA 



,Q (El'ICOROLLIA 



1 SYNANTHERIA 

 [ I] f EPICOROLLIA 

 ( CORISANTHERIA 



12 EPIPETALIA 



13 HYPOPETALIA 



14 PERIPETALIA 

 lo DICMNTA 



Examples 

 Fungi. 

 Oats. 

 Iris. 

 Orchis. 

 Aristolochia 

 Ifiimc.v. 

 Amaranth. 

 Delladonna. 



Campanula. 



Cornflower. 



\Elder. 



Carrot. 

 Manvacuhu. 



Strawberry. 

 Nettle. 



The successors of A. L. de Jussieu have followed in his path, but have differed 

 as to the relative value of his characters ; and it has further been shown that single 

 characters of great importance may in certain cases be equalled, or even surpassed, 

 by several characters of secondary importance : here quality is replaced by quantity, 

 much as twenty sous are equal to one fran,c. 



It may, however, be considered as proved, that the most constant characters 

 should rank the highest : now this constancy especially prevails in the reproductive 

 organs, and in accordance with the importance of their functions ; therefore the 

 floral organs have been rightly chosen to group species into genera, genera into 

 families (or orders), and these into classes. As regards constancy of characters, the 

 reproductive organs observe the following order: the number of cotyledons, the 

 cohesion or separation of the petals, the insertion of the stamens, the presence or 

 absence of albumen and its nature, the direction of the radicle, the aestivation, the 

 degree of symmetry in the position, number, and form of the floral whorls, &c. 



In addition to the preceding synoptical tables, it is well to give the Arrange- 

 ment of A. P. de Candolle, as followed in his ' Prodromus of the Vegetable 

 Kingdom ; ' the Classification of Ad. Brongniart, according to which the Botanical 



