6o SUMMARY. [chap. 



11. Upon characters aftbrded by the flower, of subor- 

 dinate importance (because less constant) to those which 

 distinguish Dicotyledons from Monocotyledons, botanists 

 divide each Class into Sub-classes and Divisions. The kind 

 of characters upon which these Sub-classes and Divisions 

 rest we are already familiar with, having examined repre- 

 sentatives of each. The Divisions are further divided into 

 numerous Orders. These are treated of in subsequent 

 lessons. The Sub-classes and Divisions may be synopti- 

 cally arranged thus : — 



12. Dicotyledons are, in respect of envelopes of the 

 flower — 



Dichlamydeous {Dichla77iydece\ as Poppy, Mustard, Rose, 



Melastoma, Zinnia, Rose Periwinkle, Basil, — or 

 Incomplete {Incompletce). If incomplete, either 



Monochlamydeous {Monochla7?iydece), as Grass - cloth 



Nettle, — or 

 Achlamydeous {Achlamydece)^ as Willow. 



Dichlamydeous flowers are either 

 Polypetalous {FolypefalcB), as Poppy, Mustard, Rose, 



Melastoma, — or 

 Gamopetalous {Gamopetal(Z)^ as Zinnia, Rose Periwinkle, 



Basil. 



Polypetalous flowers have their stamens inserted on the 

 receptacle (hypogynous), and are hence called — 

 Thalamifloral(77^^/a;/^^d?r^), as Poppy and Mustard, — or, 

 inserted upon the calyx (perigynous or epigynous), and 

 are hence called — 

 Calycifloral {Calycijlorce), as Rose and Melastoma. 



13. Monocotyledons have their flowers, often imperfect, 

 and with or without a minute, scaly perianth, arranged upon 

 a spadix, hence called — 



