Prepare specimens commonly used preservative fixed drug, what disadvantages? Glycerol: glycerol scientific name, is a colorless, transparent, odorless, viscous liquid with a sweet. Disadvantages: a poor low concentrations of glycerol permeability, the preparation of a mixed preservative fixative, and also reduce the rate of penetration of other drugs. Processed specimens take longer to apply. 2. High concentrations of glycerol, viscous, and have a great resistance to injection. Specimens produced by glycerol, sticky slippery stagnation herbarium custom, anatomical maneuver. To make up for the shortcomings of poor glycerol permeability of plant specimens show, someone found from polyols in better penetration sorbitan alcohol instead of glycerol, which share the herbarium and alcoholic solution, will enhance the penetration penetration properties. Should pay attention to what issues were bryophytes specimen collection? (1) bryophytes with spores, when collected, should strive to be taken to the birth sporangium plants; (2) if there is a long stem prostrate on the ground, it must be taken down. Bryophytes often grow on tree trunks, branches, bark, twigs together which would be even picked. Bryophytes and some solitary, some several Mixed, every effort should be made so that each one specimen were collected, numbered. Sporangium no mature sperm is egg does not grow into some mining should also be appropriate. This study morphological development is useful. (3) After a good specimen was collected, to one kind of an earth were wrapped in paper and placed a soft tray, do not clip, not pressure, maintaining their natural state. Natural herbarium | herbarium | voyage teaching provided by Xinxiang City Teaching Equipment Co. voyage. Xinxiang City voyage Teaching Equipment Co. (www.xxyuanhang.cn) strong, credible, in Xinxiang specimen model industry has accumulated a large number of loyal customers. The company better work attitude and constantly improving innovative ideas will lead the voyage into the brilliant teaching and you work for a better future!