SCHIZOGENIC PASSAGES. 255 
The intercullar resin-receptacles are widely distributed in the 
Coniferw; here they are found not only in the bark (Fig. 181), 
but also in the wood (Fig. 180), in the scales of the cones,’ and, 
indeed, the leaves mostly contain two of them (Fig. 179) on the 
lower surface. It is only in a few Conifer (Zazrus) that they 
are entirely wanting. 
Copal is also produced in schizogenic secretion-receptacles, 
in the Trachylobium as well as in the Hymenea, as Héhnel has 
shown. 
Fiq, 179.~Transverse section through the oil-canal of a coniferous leaf: dc, oil 
canal; s, nucleus-sheath (consisting of bast-cells) surrounding the same; sp, stoma; a, 
respiratory cavity; ep, epidermis (Tschirch). 
_ Although a longitudinal section through the root structures 
of the Composite and Umbellifere does not reveal either a 
regular arrangement* ora connection of the balsam-passages — 
1 Hanausek, ‘‘ Ueber die Harzginge in den Zapfenschuppen einiger Co- — 
niferen.” Jahresbericht der, etc., Handelsschule in Krems, 1880, 
? With regard to the distribution of the resin-passages, compare Han- 
ausek, ‘ Zur Lage der Harzgange,” Irmischia, ii. (1882), Nos. 3, 4, and 
HAG Utiler, Tinie ee es 
