Fig. 18. — Cross-section of the pith of a very old haustorium. The wall 

 swollen into yellowish substance, x 350. 



Fig. 19. — Axial part of the haustorium two years old on Bhododendron 

 sinense, diagrammatically shown in cross-section, a, neck of the 

 haustorium near the mother-root, the vessels of which are faintly 

 divided into two groups ; b, middle portion of the neck with vessels 

 scattered among parenchyma. Each vessel is shown by a dot ; c, 

 bottom of the vascular strand with compactly arranged vessels on the 

 periphery and isolated vessels in the central part ; d, base of the 

 strand with an elliptical form ; e, middle portion of the strand. 

 The strand is divided into two parts, each assuming a flat band ; 

 /, more frontal portion, co, cortical part ; ax, axial part ; st, striated 

 band ; g, apical portion, the vessel in the periphery being shown in 

 longitudinal section, iv, chains of vessels. The dot in all sections 

 stands each for an isolated vessel, x 8. 



Fig. 20. — Cross-section of the axial part of a very old haustorium, showing 

 annual rings, a, basal ; b, middle ; c, frontal ; d, apical portion. 

 x4. 



Fig. 21. — Longitudinal and cross-section of an old haustorium and Abies- 

 root (Fig. 4. a) respectively, showing the duramen in both of them. 

 cd, alburnum of the haustorium ; dr, duramen of the haustorium ; 

 cd', alburnum of the host ; dr', duramen of the host. Magnified. 



