STRUCTURAL BOTANY. 7 



produce new cells in the same. These (the progeny) es- 

 cape by the decay of the mother-cell (or niother- plant). 

 Sed Snow is an instance of this. It occurs on damp 

 rocks, in the form of dull crimson patches, which resemble 

 blood-stains. These patches consist ot numerous indivi- 

 duals of the species Protococcua nivalis, which can not be 

 seen without the microscope. 



E. PHJENOGAMS. 



How THEY DiFFKB FEOM CeTPTOGAMS GpNEEAI. CoN- 



SIDEEATION OF THE FlOWEE SoETS OF FlOWEES ThE 



Ph^nogamous Oedees of the Noetiieen and Middle 

 States East of the Mississippi, abeanged according 

 TO a Natueal System — The Aetifioial System of 



LlNNJSCS. 



26. The entire vegetable kingdom has two principal 

 divisions : Floweeless Plants or Ceyi'togams, and Flow- 

 EEiNG Plants or Pii^enogams. 



27. The Flower is a system, of organs wJdch performs 

 the reproduction of the Phcenogams. The Cryptogams 

 have no flowers. 



28. In Cevptogams, the organs of reproduction are 

 apparatus, more or less analogous to flowers, which pro- 

 duce, instead of seeds, minute bodies called Spores, that 

 do not contain any embryo prior to germination. The 

 cryptogams are lower in grade than the phfenogams. 

 They are variously classified. 



"We may distinguish Yascular and Cellular Cryptogams. 



Yasctdar cryptogams, also called Aorogens,a,ve flowerless 

 plants with a distinct axis, a branched stem, which grows 

 from the summit only, containing woody fibres and vascu- 



