Random examples of online collections of primary sources: 1  American Memory: Historical Collections for the National Digital Library. 2  Making of America: the Cornell University Library MOA collection. 3  Science Direct. 4  United States Historical Census Data Browser. 5  Valley of the Shadow: Two Communities in the American Civil War.
A vascular bundle is a part of the transport system in vascular plants. The transport itself happens in vascular tissue, which exists in two forms: xylem and phloem.Both these tissues are present in a vascular bundle, which in addition will include supporting and protective tissues.The xylem typically lies adaxial with phloem positioned abaxial. In a stem or root this means that the xylem is closer to the centre of the stem or root while the phloem is closer to the exterior.he transport itself happens in vascular tissue, which exists in two forms: xylem and phloem. Both these tissues are present in a vascular bundle, which in addition will include supporting and protective tissues. The xylem typically lies adaxial with phloem positioned abaxial.
Top of Page Secondary Stem Tissues: In dicots and gymnosperms the majority of the plant tissue is composed of secondary vascular tissues. Top of Page Vascular Cambium: The vascular cambium is a layer of meristematic tissue that lies between the primary phloem and primary xylem.As the vascular cambium adds new xylem cells toward the inside of the stem and phloem cells toward the outside of the stem, the vascular bundles eventually coalesce to form a complete ring.op of Page Secondary Stem Tissues: In dicots and gymnosperms the majority of the plant tissue is composed of secondary vascular tissues. Top of Page Vascular Cambium: The vascular cambium is a layer of meristematic tissue that lies between the primary phloem and primary xylem.