Good pasture grounds are only found near the streams. The soil is dry gravel and clay, upon which bushes of Ephedra, Nitraria and Salsolaceae grow sparsely.
The three existing genera, usually spoken of as members of the Gnetales, differ from one another more than is consistent with their inclusion in a single family; we may therefore better express their diverse characters by regarding them as types of three separate families-0) Ephedroideae, genus Ephedra; (2) Welwitschioideae, genus Welwitschia; (3) Gnetoideae, genus Gnetum.
The genus Ephedra, with its prothallus and archegonia, which are similar to those of other Gymnosperms, may be safely regarded as the most primitive of the Gnetales.
In some species of Ephedra, e.g.
In Ephedra helvetica, as described by Jaccard, no proembryo or suspensor is formed; but the most vigorous fertilized egg, after undergoing several divisions, becomes attached to a tissue, termed the columella, which serves the purpose of a primary suspensor; the columella appears to be formed by the lignification of certain cells in the central region of the embryo-sac. At a later stage some of the cells in the upper (micropylar) end of the embryo divide and undergo considerable elongation, serving the purpose of a secondary suspensor.
The secondary wood of Ephedra consists of tracheids, vessels and parenchyma; the vessels are characterized by their wide lumen and by the large simple or slightly-bordered pits on their oblique end-walls.
In Gnetum Gnemon, as described by Lotsy, a mature embryo-sac contains in the upper part a large central vacuole and a peripheral layer of protoplasm, including several nuclei, which take the place of the archegonia of Ephedra; the lower part of the embryo-sac, separated from the upper by a constriction, is full of parenchyma.
The structure of the wood agrees in the main with that of Ephedra.
(1899); Land, " Ephedra trifurca," Bot.
HORSETAIL (Equisetum), the sole genus of the botanical natural order Equisetaceae, consisting of a group of vascular cryptogamous plants (see Pteridophyta) remarkable for the vegetative structure which resembles in general appearance the genera of flowering plants Casuarina and Ephedra.
Certain herbs such as lobelia, ephedra and others with strong side effects are restricted to licensed, trained herbalists only.
Shrubby Horsetail (Ephedra) - Curious greyish, wiry, trailing bushes of S.
The herbs most frequently mentioned in these case reports are aconite, ephedra, and licorice.
Because ephedra can cause severe cardiac side effects, the Food and Drug Administration has issued warnings against its use.
Ephedra, also known as Ma-huang, grows mostly in Asia.
Synephrine works like ephedra as a stimulant and should be used with caution.
Ephedra has been banned in the United States due to its dangerous effect on blood pressure and heart rate.
Bitter orange behaves similar to ephedra and should be used with caution.
Ephedra was taken off the market a few years ago due to several deaths associated with its use.
Some herbs can have serious side effects and should be avoided all together, such as ephedra and fen-phen products, which can significantly increase blood pressure, heart rate, and overall stimulation of central nervous system.
There have been two known deaths directly related to the use of ephedra.
The natural herb ephedra has caused a fair bit of controversy.
Many of those struggling with obesity, who have been studied, could eat whatever they wanted, exercise a moderate amount and still lose weight while taking ephedra.
It works by stimulating your body's motivation to burn more fat, and works with caffeine much like ephedra.
However, other supplements can be dangerous, such as ephedra, which has been linked to raised heartbeats.
The FDA confirmed that ephedra use raised blood pressure and otherwise stressed the circulatory system long before it was pulled from the shelves.
It all took time, and in the meantime people bought and used OTC products containing ephedra.
The FDA now bans supplements containing ephedra and other harmful substances.
However, certain alkaloids present in the herb work similarly to the ephedrine found in ephedra, making some individuals doubt its safety.
The word usage examples above have been gathered from various sources to reflect current and historial usage. They do not represent the opinions of YourDictionary.com.