Barley

This picture shows a plant, which everbody saw a million times: the barley (Hordeum vulgare L.). As many other userful plants it belongs to a plant familiy, which is often -above all because of the construction of its flowers- considered as the most modern and most derived plant family: The grasses (Poaceae, formerly called Graminae).

A typical leaf of such a grass consists of two parts: a long, tubular, stem-clasping sheath, which forms a knot at its base, and a long blade. At the transition between sheath and blade there is in most cases a membraneous appendage, the "ligula". In the case of the barley the ligula consists of a stem-clasping eye, which can be seen on the picture. Above it there is the node of the next leaf.