1917] FAUST—RESIN SECRETION 479 
ments, and sclerified stele; inulin deposits in outer cortex granular; in inner 
cortex, sphero-crystals; mx, metaxylem; ph, phloem; c, cambium; sch, 
sclerome; en, endodermis; hy, hypodermis; e¢, epidermis; X150. 
IG. 18.—Section through old subsidiary root, showing formation of resin 
canals in region of endodermis: rc, resin canals; 150. 
1G. 19.—Detail of sections of stone cells: a, section at edge of cell showing 
unsclerified pores; b, border of internal opening; c, d, through center of cells; 
a, 6, d, longitudinal sections; c, transverse sections; 300. 
IGS. 20—-23.—Sections Sf itcraile critical levels of a 2 mm. seedling: fig. 2 
region of hypocotyl; fig. 21, lower cotyledonary collar; fig. 22, upper ae 
donary collar; fig. 23, iver reaches of cotyledons; w, x, y, 2, primary bundle 
traces in hy pocetyl: p, r, s, t, secondary bundles of cotyledonary collar; white 
areas in sacs phloem; black areas, xylem; dotted areas, metaxylem; X60. 
Fic. 24.—Longitudinal diagram of bundle traces in region of hypocotyl 
and lower epicotyl, reduced to one plane: k, m,n, 0, primary traces of epicoty]; 
other designations as in figs. 20-23. 
Fic. 25.—Transverse section through peduncle: 9, pith; c, cortex; 7, 
resin sate of outer series; r2, resin canals of inner series; 150. 
Fics. 26-30.—Cross-sections of resin canals of root at various stages of 
Pe asa fig. 26, first periclinal division of initial endodermal cell; fig. 27, 
first oblique division; figs. 28, 29, progressive stages in formation; fig. 30, 
fully developed canal; Ca, Casparian thickening; 150 
IG. 31.—Transverse section of old root (4 or 5 years), showing two series 
of canals ie radial anastomoses; Xt. 
Fic. 32.—Longitudinal ictal section of fully aig ty canal; X150. 
PiG. | 33 et hidon? of young seedling in ese tae deel 
region, showing radial a moses of two series of his canals in root system 
rr, Outer series; 72, inner cue: a, radial canals. 
Fic. 34.  Scheneae diagram*from sections, illustrating extent and con- 
nections of resin canals of 5 mm. seedling, in region of hypocotyl: r:, outer 
series of canals; r2, inner series of canals; a, radial canals. 
Fic. 35. 2 Section through origin of resin canals of stem: a, initial canal 
cell in process of division; }, cells dividing a second time; ¢, d, subsequent 
divisions to form canals; 300. 
1G. 36.—Section of 3-year-old root, stained to mae distribution of inulin 
and resin: si, sphero-crystals of inulin; r, 7, resin deposits. 
Fic. 37.—Detailed sketch of inulin, resene, and resinic acid: a-d, wi 
pith cell of stem; e, f, deposited from evaporation of alcoholic solution; a, 
crystal of inulin; i; crystals of resene within cell; c, d, resene crystals im ee 
in resin masses; e, detail of resene crystal; /, resene crystal imbed 
masses; 150. 
