1917] FAUST—RESIN SECRETION 475 
they are laid down. Such seems to be the significance of the pene- 
tration of the phloem strands into the cortical areas through the 
Casparian strip (fig. 13). 
Much emphasis has been placed by Tscutrcu (loc. cit. p. 1118) 
on the non-permeability of resinic acid through cell walls. This 
author contends that resin is laid down where it is formed. Yet in 
an alkaline medium, such as is frequently if not always found in 
growing tissues, an unstable resin ester would be formed, un- 
doubtedly capable of penetrating cell walls. Then, too, the fact 
remains that a considerable part of the resin forms in the meristem 
and ‘is transferred to the canals, else it would never get to the 
canals. Such a transfer could be accomplished in the form of a 
temporary ester. On the other hand, the microchemical observa- 
tions show that the larger amount of the product is transferred as 
balsamoresene and changed to the acid in the vicinity of the cells 
immediately surrounding the canals or in the canals themselves. 
There is even evidence to support the view that inulin may be 
changed into resene and later into resinic acid in the vicinity of the 
canals. In fact, such a change is actually shown in progress in 
fig. 36. There seems to be no specific way for the translocation of 
the by-products to the resin ducts. It may be accomplished by a 
temporary ester formation, or by the translocation in the form of 
balsamoresene, and later changed into resinic acid, and it may be 
centrifugally distributed as a fractional depolymer of inulin, and 
consequently changed to resene and resinic acid near the canals. 
Any one of these means would satisfy the needs of a translocation 
in a dialyzable form. 
Summary 
1. Balsamorrhiza sagittata is the dominant member of its habitat 
in the inter-mountain region. The plant depends largely upon 
growth of the rootstock for propagation. It does not produce 
flowers until the third or fourth season. A hardy rootstock 
accounts for its dominance, since the viability of the seeds is small, 
due to parasitic infection. 
2. The radicle has the tetrarch type of development. The 
resin canals of the root arise in two concentric rows above and 
