PLATE 39. Vegetable Tissues. 



Figure 



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



the walls of two contiguous pitted wood-cells. 



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



b, 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 of Araucaria imbricata. 



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



7. Wood-cells of Mammillaria, with broad spiral bands. 



8. Spiral and annular vessel of Rhubarb. 



9. Reticulated duct from the same. 

 Scalariform duct of a tree-fern. 



End of a spiral vessel of the white lily. 

 Fragment of a larger and looser one. 

 Pitted duct of the lime (Tilia parvifolia). 



14. Wall of a pitted duct of Cassyta glabella. 



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



16. Wall of a pitted duct of Laurus Sassafras. 



17. Wall of a pitted duct of Chilianthus 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 of Euphorbia antiquorum ; the latex containing starch- 



grains of peculiar shape. 



. - , i - i -, /v. i., /> 



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



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



b, 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 of 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), with fine spiral striae. 



31. 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 Coniferse. 



