BY D. MCALPINE. 625 



branching inwardly and covering the seed-cavity with a fine 

 network of vessels, and liranching outwardly towards the surface. 



Fig. 10. — Transverse, median section of core, showing the flower-like 

 arrangement of tlie carpellary walls, and the ten primary vascular 

 bundles associated with them. 



Fig. II. — 'IVansverse section of stalk just as it enters the fruit, showing the 

 ten fibro-vascular bundles. At this level, there were four bundles 

 single, and the remaining six formed three pairs. At the base of 

 the core, they broke up into ten distinct vascular bundles, as 

 shown in the next figure ( x 30). 



Fig. 12. — 'I'ransverse section of stalk, where the vascular bundles diverge, 

 showing ten strands radiating from it. 



Plate xxiv. 



Fig. 13. — Surface-view of epidermis, showing the thick-walled mother-cells 

 divided into the thinner-walled daughter-cells, known as 

 " window-cells," from their appearance ( x 100). 



Fig. 14. — Surface-view of epidermis, with the contents of the daughter-cells 

 retained ( x 100). 



Fig. 15. — Cross-section through the skin of an apple, showing the epidermis 

 and hypodermal layer into whicli the ultimate branchlets of the 

 vascular bundles penetrate. There is the cuticle of the epidermis, 

 about 12 jx in thickness, standing out clearly, and surmounted by 

 a thin deposit of wax ; the brick-shaped epidermal cells, and 

 usually four or more la3ers of cells in the hypoderm tangentially 

 elongated ( x 100). 



Fig. 16. — Transver.se section of a fibro-vascular bundle, showing the xylem, 

 with numerous vessels below, and the phloem with sieve-tubes 

 above. The parenchj'inatous cells of the flesh adjoining the 

 vascular bundle are usuallj^ narrower, and smaller than the 

 •ordinary cells ( x 100). 



Fig. 17. — Longitudinal section of vascular bundle, showing the spiral 

 vessels of the xyleni ( x 100). 



Fig. 18. — Leaf of apple showing midrib, with diverging veins and veinlets 

 forming a network. Tiie number of vascular bundles entering the 

 petiole is three. 



Plate xxv. 



Fig. 19. — Oblique view of apple, with the outer flesh removed, showing the 

 enveloping network of vascular bundles, with the projecting, 

 plume-like branches arising from the strands of eacli mesh. 



Fig.20. — Plume-like branches, slightly enlarued. 



Fig.'21. — (ieueral view of network and plume-like branches, with some of 

 the flesh still adhering to the " eye "-end. 



