62 PHARMACEUTICAL BOTANY 
Internal glandular-hairs with greenish oleoresin contents are 
frequently to be discerned projecting into many of these spaces. 
3. XYLOCENTRIC VascuLAR BUNDLES or laminar veins, that 
distribute sap to, and carry sap from the mesophyll. These are 
Fic. 34.—Structure of the Fern Pinnule. (Dryofteris Fititiivas) A, lower 
epidermis in surface section. B, upper epidermis in surface section. C cross 
section of mid-vein and adjacent interneural ions of lamina D, cross aii: 
of marginal region. 2, epidermal cells below a vein; st, stoma; ge. aco cells; n 
nucleus; c, chloroplastid; sv, sap vacuole; chi, chlorenchyma; nal Sis, iia: ‘§ 
internal glandular hair; a, intercellular-air-space; St, sieve dieitic ay. . 
xylem; fe, pericycle; en, endodermis; uep, upper epi is: ty 
se ih Pidermis; mes, mesophyil; lep, 
seen to be embedded in the chlorenchyma of the mesophyll 
The xylem portion of each te is nearest, in end re <a f 
veins, to the upper surface of the leaf cence 
and so 
approach the collateral type. wet Bie bundles there 
