324 THE CLASSIFICATION OF PLANTS 



lichens and toad-stools, the bodies of which are of simple 

 construction and exhibit no differentiation into stem, root and 

 leaf. When branching does take place, the members produced 

 are usually all essentially alike, and resemble the previously 

 existing parts from which they arise : the body of a plant of 

 such simple structure is termed a thallus. In some instances 

 each plant is very minute, being merely a single cell, while in 

 others, the thallus consists of thousands of cells : in all cases, 

 however, the cells possess a distinct cell-wall. 



The Thallophytes are divided into several sub-divisions of 

 which two, namely, the Schizophyta and the Fungi are of 

 great practical importance : the former includes the Bacteria 

 or Schizomycetes. 



Division III. — The Bryoplijrtes comprise two classes of plants, 

 namely, liverworts and mosses. 



Division IV. — The Pteridophytes include ferns, horsetails 

 and club-mosses. 



Some of the above divisions of the Vegetable Kingdom, such 

 as those including the sea-weeds, mosses and ferns, are without 

 practical interest or importance for the farmer, and want of 

 space prohibits more than a mere mention of their existence. 

 Students wishing for information in regard to those divisions are 

 referred to the ordinary text-books of systematic botany. 



The Bacteria and Fungi, however, which are included in the 

 Thallophyta, need special attention on account of their practical 

 bearing, and are dealt with in subsequent chapters. 



Division V. — The Spermaphjrtes or- Phanerogams include all 

 those plants which produce seeds. This division is split up into 

 two sub-divisions namely : — 



Sub-division i. — Gymnosperms. 

 and Sub-division 2. — Angiospems. 



In the Gymnosperms, of which the cone-bearing firs and pines 

 are examples, the carpels are flattened structures and the ovules 



