344 BOTANICAL GAZETTE [ NOVEMBER 
Fic. 7. One of the outer and exposed normal bud scales, fringed with the 
marginal hairs, which are thin walled and filled with resin. 
Fic. 8. Cross section of a normal bud scale with four resin canals. 
_ Fic. 9. Cross section of a normal bud scale with two resin canals. 
Fic. ro. Longitudinal section at the base of a bud of a normal shoot: 
a, cambium, with phloem and xylem cells; 4, base of the annulus, or wall of 
the cup, surrounding the growing point in winter; c, base of the inner bud 
scales, composed of thick walled collenchymatous cells, similar to those of 
the annulus and pith septum; d@, parenchyma of the primary cortex; ¢, part 
of pith septum, with irregular 3~-4-sided prismatic cells; f, pith cells; 
g, loosely connected rounded pith cells, which break away from the septum 
in older internodes, forming the pith chamber. 
PIG. 11. Epidermal hairs on a normal one year old lateral shoot. 
IG. 12. One of the detached resin vesicles of the primary cortex, magni- 
fied about four diameters: a, remnant of the original resin canal from which 
the resin vesicle developed. 
1G. 13. Cross section of the thin membrane covering the resin vesicle: 
a, thick walled, elongated or stretched cells of the membrane; s, thin walled 
epithelial cells lining the membrane of the vesicle on the inside; 4, one of 
the epithelial cells dividing radially ; c, one of the epithelial cells dividing 
tangentially ; ¢, primary cortex ; e, parenchyma cells of the primary cortex 
torn loose from the resin vesicle membrane, which has elongated or increased 
in size peripherally. . 
Fic. 14. Cross section of the wood of a diseased branch about 1™ below the 
middle of the tumor, showing two abnormal vertical resin canals: a, an 
in-grown epithelial cell, filling up almost the entire lumen of the resin canal 
(ty losis). 
