SYNOPSIS OF THE NATURAL ORDERS 



(ADAPTED TO THE BRITISH GENEEA). 



THE arrangement here adopted adheres very closely to the Jus- 

 sieuan as modified by De Oandolle, which, notwithstanding its many 

 defects (inseparable from a linear arrangement), is, I think, as good as 

 any of those subsequently proposed,* and has the great advantage of 

 being that most generally adopted in the Universities and Schools of 

 Great Britain and America, and in systematic works everywhere. Its 

 great defect is the necessity of an Apetalons division, embracing a hetero- 

 geneous mass of Orders, which have rarely any mutual affinities, and 

 are incapable of being naturally grouped. Some of these are obviously 

 allied to Polypetalous or Monopetalous Orders, but cannot be placed in 

 contiguity with these without interfering with other and closer alliances ; 

 some again present cross affinities with two or more often distant Orders ; 

 and the greater proportion have no ascertained affinities. Under these 

 circumstances, and seeing how much the retention of the Apetalous 

 division facilitates the often difficult task of finding the Natural Order of 

 a plant, it appears to me to be premature to depart from the Jussieuan 

 system. 



CLASS I. DICOTYLE'DONS. 



Stem when perennial, with pith, one or more concentric layers of woody 

 tissue and a separable bark. Leaves usually net-veined. Whorls of the 

 pirianth in 4's or 5's. Embryo with 2 cotyledons ; the radicle itself usually 

 elongating in germination. 



DIVISION I. Polypet'alse. 



Plotters with both calyx and corolla (dichlamydeous). Petals free. (See 

 also the exceptional Monopetalce.) 

 Exceptions : Flowers wanting either calyx or corolla occur in : 1, RANUNCU- 



LACE.E ; 6, CRUCIFEBJE (5 C'ardamine, 16 Senebiera, and 17 Lepidiuni); 



9, VIOIACEJE (apetalous forms of Viola) ; 12, CARYOPHYLLE.S; (8 Arenaria 



Cherleria, 9 Sagina) ; 14, PARONYCHiKjE (2 Herniaria, 4 tkleranthus) ; 



27, ROSACE* (8 Alchemilla, 10 Poterium); 28, SAXIFRAGES (2 Clirysosple- 



nium) ; 31, HALORAGE.E ; 32, ONAGRARIEJE (2 LuiUrigia) ; 33, LYTHRACE.E 



(2 Peplis). 



* Of these the principal are : that of Brongniart, adopted in the Paris Schools ; of 

 Enrtlicher, in many of the German Schools ; of Fries, by various botanists in Scandi- 

 navia ; and of Lindley (" The Vegetable Kingdom"}, which has been partially followed 

 in England and India alone. 



