Page 183 - Pharmacognosy 2 PG303 (1)
P. 183

Pharmacognosy-2 (PG303)                              Level 2                Clinical Pharmacy-Pharm D

              distinct continuous dark cambium ring, and a wide central part, usually paler than
              the  bark,  with  numerous  dark  islets,  surrounded  by  tertiary  cambia,  also  with
              irregular lines of tertiary cambia which sometimes even form complete rings, and
              dark points of resin cells. Jalap has a slight, characteristic, and somewhat smoky
              odor and a sweetish, then acrid disagreeable taste.






























              Microscopical Characters
                     Cork, dark brown almost black, or numerous layers of brown thin-walled
              cells, phloem, parenchymatous, constituting mostly the whole of the bark, rich in
              cluster crystals of calcium oxalate and in starch, and with numerous resin cells in
              longitudinal rows, and scattered isolated sclerieds with thick, pitted walls, especially
              near  the  cork,  secondary  xylem,  constituting  the  whole  part  inside  the  main
              cambium ring, formed mainly of parenchyma containing starch granules and cluster
              crystals of calcium oxalate, showing'' very narrow radiating area of vessels in short
              radial  rows  near  the  cambium,  and  exhibiting  numerous  abnormally  formed
              concentric  bundles  of  few  vessels  surrounded  by  tertiary  cambia  and  phloem.
              containing numerous resin cells and vessels.


























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