DIVISIONS OF THE NATURAL SYSTEM, 



AS ADOPTED IN THE PRESENT WORK. 



Division A. PHANEROGAMOUS or flowering plants. 



CLASS I. 



DICOTYLEDONS on EXOGENS. 



Embryo furnished with two opposite cotyledons, rarely more, 

 and then much divided or whorled. Stem increasing by external 

 layers. Leaves with branching veins, the ultimate ones reticu- 

 lated. Flowers arranged in 5 or 2 parts, or multiples of these 

 numbers. 



SUB-CLASS 1. THALAMIFLOR^E, . . . Page 1. 



Petals several, distinct, and are, as well as the stamens, 

 inserted into the receptacle (hypogenous) below the ovaries. 



SUB-CLASS 2. CALYCIFLOR^G, .... Page 36. 

 Petals several, distinct, and are, as well as the stamens, 

 inserted into the calyx (perigynous). 



SUB-CLASS 3. COROLLIFLORJE, . . . Page 78. 



Corolla with the petals united (monopetalous). Stamens 

 mostly inserted upon the corolla (epipetalous). 



SUB-CLASS 4. MONOCHLAMYDE^E, . . . Page 136. 

 Perianth single or none. 



SUB-CLASS 5. GYMNOSPERM.E, . . . Page 154. 

 Ovaries open, destitute of style or stigma. Perianth none. 



CLASS II. 



MONOCOTYLEDONS on ENDOGENS, . . . Page 155. 

 Embryo furnished with one cotyledon, or, if more, alternate. 

 Stem increasing and lengthening by new matter within ; woody 

 bundles confused. Leaves parallel-veined and withering on the 

 stem. Flowers arranged in 3 parts or multiples of this number. 



