1917] FAUST—RESIN SECRETION 467 
it as the crystallized inulin, a colloidal polysaccharide. In ordinary 
growing tissues these crystals are deposited in a viscous lemon- 
yellow mass, but in alcohol they undergo certain changes in shape. 
In readily permeable tissues they are laid down as granular masses, 
but where there is slow alcoholic penetration they are laid down as 
sphero-crystals. Such crystals are well illustrated and their loca- 
tion shown in fig. 36 (si). They are found in connective tissue, 
especially in the rays and in the inner cortex. In this same speci- 
men the canals are filled with resin. The semiviscous, semigranular ° 
resene is well brought out in fig. 16, the section of a very young 
subsidiary root without secondary thickenings yet developed. In 
fig. 17, the section of a subsidiary root further developed, is shown 
in the more permeable outer region of the cortex the semiviscous, 
semigranular inulin, while the sphero-crystals are found in the 
inner cortex, not so permeable to alcohol. 
Other observations on the growing stem buds showed the follow- 
ing relationships. Young etiolated stem buds showed no inulin, 
while green stem buds were filled with inulin. Such observations 
are proof that the result of the photosynthetic process in B. sagit- 
tata is inulin. Such a substitute for starch is found in the related 
Compositae, Helianthus annuus, Inula Helenium, and for roots of 
Dahlia spp. 
As the microchemical tests progressed, evidence became 
stronger that a genetic relationship existed progressively in turn 
between each two of the three products found in Balsamorrhiza, 
namely, inulin, resene, and resinic acid. The hypothesis built up 
on this evidence may be stated thus: 
Inulin<resene<resinic acid; in other words, inulin, a poly- 
saccharide, formed in the plant in the process of photosynthesis, 
by a process of polymerization is changed to resene, and by reduc- 
tion the resene is altered to resinic acid, a waste product of the 
plant. The direct evidence supporting this view may well be 
summarized at this point: (1) etiolated stem buds contain neither 
inulin nor resene, while green leaves test for both coincidentally; 
(2) resene and resinic acid are found in the stem and root at the 
same time; resene more frequently occurs in conductive tissue and 
