XVI International Botanical Congess

The stem bark anatomy in Linnaea borealis L. was studied. This small, spreading shrub has thin stems, covered by simple 1-cellular trichoms. The primary bark includes 3-4 layers of parenchyma. At the early stages of development epiderma and primary bark deformate and external part of the bark exfoliates. The primary phloem is represented by the entire ring of large fibers with feebly thickened walls. Phellogen originates under the ring of protophloem fibers. The 3-5-layer secondary phloem in perennial stems includes sieve tubes, companion cells and parenchyma, containing starch. The second phellogen doesn+t originate. Linnaea differs from other Caprifoliaceae by anatomical features: secondary phloem without lignificied elements, 1- layer ring of thin-walled protophloem fibers, abcense of oxalate calcium crystals and only one periderma. Perhaps, Linnaea must be placed in taxon of the higher rank.