78 MICROSCOPICAL RESEARCH 



PLATE IV. 



STEM STRUCTURE. 



Fig. 11. Transverse section. Stem of Marestail. ' Hippuris vulgaris ' 

 xl5dia. Fixed in Chro mo- Acetic solution. Stained Borax 

 Carmine and Malachite Green. 1. Cortical tissue. 2. Central 

 axis of stem. 3. Xylem elements. 4. Cambiform tissue. 

 5. PUoem elements. 



Fig. 12. Transverse section. Stem of Limnanth ' Limnanthemum 

 nymphseoides ' x 20 dia. Fixed in Chromo-Acetic solution. 

 Stained Hsematoxylin and Safranin. 1. Cortical tissue. 



2. Idioblasts. 3. Intercellular space. 4. Xylem elements. 

 5. Central axis of stem. 6. Primary ground tissue formed 

 of radialy elongated cells. 



Fig. 13. Transverse section of Sunflower. 'Helianthus annuus' 

 X 20 dia. Fixed in 92% Alcohol. Stained Borax Carmine 

 and Malachite Green. 1. Cortical tissue. 2. Primary 

 ground tissue. 3. Cambium ring. 4. Xylem elements. 

 5. Phloem elements. 



Fig. 14. Tangential longitudinal section. Stem of Sunflower. 

 'Helianthus annuus ' x 65 dia. Cut ^/ 1200 in. The line of 

 cut passing through the inner margin of a primary bundle. 

 1. Primary ground tissue. 2. Fibro-vascular bundle. 



3. Spiral vessel. 



