Page:The Oak.djvu/84



17.—Transverse section of cortex and phloëm of oak (highly magnified). k, the periderm (cork), which has replaced the epidermis; c, collenchyma; d, cells of cortex containing crystals of oxalate of lime; s, schlerenchyma cells. All these belong to the cortex proper. Below these come the phloëm; b, b, groups of hard bast fibers; bp, phloëm-parenchyma; bs, medullary ray; e, cells containing crystals of oxalate of lime. (Luerssen.)