78 



CELLULAR TISSUE, 



Tidges. On tKe epidermis of the branches of Prumnopitys elegans ^ the process^^ 

 are very large, .in the form of thick plates, which are blunt, often branched, of 

 unequal size, and irregular curvature; so that in their sections separate pieces, 

 cut off from these, lie isolated in the njon-cuticularised membrane. On the leaves 

 of many Proteacese (Lomatia longifolia, Hakea ceratophylla, H, Baxter! **) the pro- 



FlG. 25.— (390) Transverse section through the leaf of Aloe verru- 



-cosa. a lying in water, not acted upon by reagents. The non- 

 ciiticularised parts of the membranes shaded; outside this the 



lenticular layers, broken up by darker limiting lamellae, and covered 

 by the cuticle, which has a double contour, b after warmipg with 



i potash solution. The cuticle^-r-A^ raised from the (shaded) cuticular 

 layers ; the non-cuticularised (unshaded) inner layers somewhat swol- 



'len. c epidermal cells after complete removal of the cuticle, and of 

 the cutin deposited in the cuticular layers, by continued boiling with 

 potash. They are separated frpm one another, and are seated upon 

 the cells of the sub-epiderraal parenchyma ; the cuticular layers are 



^ now only distinguishable from the others by more delicate stratiflca- 



' tion. 



Fig. 26.— {800) Ilex aquifolium; leaf. A transverse 

 section through the midrib of the under side ; a, 6 cuti- 

 cular layers, the inner (*) stains yellow with Schultze's 

 solution, and is continued into the limiting lamella, 

 which reaches to the sub-epidermal layer. The outer 

 (a) remains uncoloured in Schultze's solution (only par- 

 tially true cuticle?), c, c the non-cuticulariged portions 

 of the membranes. From Sachs' Textbook, compare 

 p. 3S'— -5 a few cells of the same epidermis, seen from 

 the outer surface. 



Fig, 27. — (800) Pinus Pinaster. Leaf, transverse sec- 

 tion, corner of the margin, c cuticularised x i inner 

 non-cuticularised layers of the epidermal cells ; c' very 

 large and thick-walled cells lying at the corner; g~{ 

 hypoderma ; p chlorophyll-containing parenchyma ; 

 pr contracted protoplasmic body of the cell with in- 

 folded walls, From Sachs' Textbook. 



cesses are blunt and swollen, and the spaces between them, which are filled with 

 cellulose, are narrow slits. These appear in surface-view as bands which are 



^ Graf zu Solms-Laubach, /; c. 



^ Nageli, Sitzungsber. d. Bayr. Acad. 7. Mai, 1864, Taf. II. 19; 20. 



