PLATE 39.— Vegetable Tissues. 



Figure 



1 . Wood of Pinus sylvestris, a, radial vertical section ; 5, tangental section of 



the walls of two contiguous pitted wood-cells. 



2. Tangental section of the wood of Casuarina equisetifolia. «, pitted wood-cells ; 



by duct ; c, cells of a true medullary ray ; d, cells of one of the concentric 

 medullary layers. 



3. Vertical section of wood-cells of box. 



4. Vertical (radial) section of wood-cells of the yew. 



5. Vertical (radial) section of wood-cells oi Araucaria imbricata. 



6. Spiral-fibrous cells from the roots of Dendrobium alatum, 



7. Wood-cells of Mammillariay with broad spiral bands. 



8. Spiral and annular vessel of Rhubarb. 



9. Reticulated duct from the same. 



10. Scalariform duct of a tree-fern. 



1 1 . End of a spiral vessel of the white lily. 



12. Fragment of a larger and looser one. 



13. Pitted duct of the lime {T ilia parvif olio). 



14. Wall of a pitted duct of Cassyta glabella. 



15. Wall of pitted ducts oi Bombax pentandra. «, next another duct; b, next cells. 



16. Wall of a pitted duct of Laurus Sassafras. 



17. Wall of a pitted duct of Chilianthiis arboreus. 



18. Wall of pitted ducts of Clematis {Clematis Vitalba). 



19. End of a spiral-fibrous duct of Daphne Mezereon. 



20. Walls of pitted wood-cells of Cycas. 



21. Fragment of the wall of a large pitted duct of Eryngium maritimum. 



22. Vertical section through the stomate of Aloe ferox. The darkly shaded part 



represents the cuticular layer. 



23. Fragment of a latex-duct oi Euphorbia antiquorum ; the latex containing starch- 



grains of peculiar shape. 



24. Epidermis of the petal of the daffodil, from above. 



25. Fragment of the leaf of Sphagnum cymbiforme. a, empty cells with spiral fibre; 



by interstitial cells with chlorophyll. 



26. Vertical section of the upper face of the leaf of Parietaria officinalis^ with a 



cystolithe. Magnified 100 diameters. 



27. A similar section from the leaf oi Ficus elastica. Magnified 100 diameters. 



28. a and b. Sections of the cellular tissue of onion-bulb, containing raphides. 



29. Stomate and epidermis of Equisetum-, the siliceous coat remaining after the 



destruction of the organic matter. 



30. End of a liber-fibre of the periwinkle {Vinca major) y with fine spiral striae. 



3 1 . Branched liber-cell of the radicle of Rhizophora Mangle. 



32. Siliceous cast of the inside of a duct of unknown fossil wood ; the peculiar con- 



centric concretions of the silica imitate to a certain extent the so-called glan- 

 dular markings of Coniferee. 



