C. ELEMENTARY TISSUES. 



TABLE OF TISSUE FORMS, OR ELEMENTARY TISSUES. 



I. PARENCHYMA TISSUE. IV. FIBROUS TISSUE. 



II. / COLLENCHYMA TlSSUE. V. TRACHEARY TlSSUE. 



III. ^SCLERENCHYMA TlSSUE. VI. SlEVE TlSSUE. 



VII. LATICIFEROUS TISSUE. 



1. PARENCHYMA TISSUE. Tissue of the FUNDAMENTAL SYSTEM, 

 forming the "ground work' 1 of plants ; with cell walls of varying 

 thickness, and although of diverse forms yet never fibrous, as dis- 

 tinguished from PROSENCHYMA. 



The more ordinary forms to be considered are : 



1. Isodiametric. 4. Irregular. 



2. Stellate. 5. .Epidermal. 



3. Ellipsoidal. 6. /Suberox*. 

 Illustration: ISODIAMETRIC CELLS from GERANIUM STEMS 



{Pelargonium inqninans), PITH of most STEMS. 



PREPARATION FIRST: A thin transection of the stem can be 

 made free hand as directed on p. 16 and mounted in water or 

 glycerin. 



ORSERVE: 1. In the center of the section, thin walled isodi- 

 ametric cells of varying size. 



2. Nuclei if present. 



3. Contents of parenchyma cells in various parts of the 

 section. 



4. The irregular spaces between the cells, Inter-cellular 

 spaces. (Fig. 12.) 



5. By careful focusing near the outer edge of the section 



