386 MANUAL OF NATUKAL HISTOKY. 



II.—SUB-KINGDOM. FLO WERLESS-PL ANTS. 



Cryptogamia, Lin. Acotyledones, Juss. Cellu- 

 lares, De Cand. Homorgana, Schultz. Esexuales, 

 Lindl 



1 Class Acrogens ..„(Pseudocotyledonea3, Agardh. 



Heteronemea, Fries. 

 Hysterophyta | ^ 



Acrobrya (partim), ) 

 Cormogense, Lindl. 

 Acrogenae, Brongn.) 



2 „ Thallogens (Acotyledonese, Agardh. 



Homonomea, Fries. 

 Cryptophyta, Link. 

 Thallophyta,* 

 Protopnyta, ) 

 Amphigense, Brongn. 

 Thallogense, Lindl.) 



FLOWERING-PLANTS. 



Among Vegetables, Sub-kingdoms cannot be 

 defined or limited with the same precision and ac- 

 curacy as among animals, for the nervous system, 

 of which the different modes of distribution serves 

 so well as the basis of primary divisions in the lat- 

 ter, is totally wanting in the other, nor do they 

 possess any other tissue which can adequately sup- 

 ply its place. Some systematical- writers, indeed, 

 discard the separation into Sub-kingdoms altogether, 

 and proceed at once to Classes, Sub-classes, and 

 Orders. But without laying too much stress on 

 such divisions, they seem to be naturally indicated, 



