94 MICROSCOPICAL RESEARCH 



PLATE XII. 



LEAF STRFCTUEE. 



Fig. 41. Transverse section. Leaf of Tradescantia. ' Tradescantia 

 discolor' X 35 dia. Fixed with. Chromo-Acetic solution. 

 Stained witli Aniline -picrate and Grossypimine. 1. Lower 

 epidermis. 2. Primary ground tissue. 3. Dense layer of 

 assimilating tissue. 4. Vascular bundle. 5. Air cavity. 

 6. Stoma. 7. Upper epidermis, showing vertical walls of 

 the cells only. 8. Mucilaginous lining of the cell. 9. Nucleus 

 of cell. 10. Upper cuticle of leaf. 



Fig. 42. Cuticle. Leaf of Monkey-puzzle. 'Araucaria imbricata' 

 x50dia. Stained with Bra,zilin. 1. Cuticularised tissue. 

 2. Stomata. 



Fig. 43. Transverse section. Green Stem of ' Casuarina equisetifolia ' 

 X 50 dia. Fixed in Chromo-Acetic solution. Stained with 

 Borax Carmine and Malachite Green. 1. Cortical tissue. 

 2. Leaf-trace bundles. 3. Cambium layer. 4. Xylem 

 elements. 5. Primary medullary ray. 6. Central axis of 

 stem. 7. Stomata bordering the stem cavities. 



Fig. 44. Epidermis and stinging-hairs from midrib of young Leaf 

 of Nettle. 'Urtica dioica' x35 dia. Fixed with Chromo- 

 Acetic solution. Stained with Borax Carmine and Malachite 

 Green. 1. Cuticularised epidermis of midrib. 2. Enlarged 

 base of sting. 3. Cavity of sting, filled with irritant fluid. 

 4. Capitate apex of sting. 5. Stiff hairs of midrib. 



