This volume is the last contribution of a series of With the present
book, a further gap concern- studies concerned with the plant material
of one ing leaf morphology and leaf venation, as well and the same area
of Venezuelan Guiana. The as some structural peculiarities of
physiological importance, is closed so that an exhaustive survey studies
originated through a collaboration with the forest engineer Dr. B.
Rollet, the FAO expert in of bark and leaf morphology and anatomy as
well forest inventory who collected the material of tree as of fruit and
seed structure of the plants of a barks, leaves, fruits and seeds in
Venezuelan certain well-known area is herewith given. Not Guiana around
the "Rio Grande", "EI Paraiso", only were hundreds of species studied,
but and "EI Dorado" camps. In the first place, tree structural
characteristics were related to "forest barks of about 280 species of
dicotyledons stratification", i. e. to the different micro climatic
belonging to 48 families were studied (family by conditions in the
forest, as the height of the trees family) by Roth in separate
publications which and shrubs studied was known. It is of common mainly
appeared in Acta Botanica Venezuelica knowledge that in the lower forest
layers, light is a and in Acta Biol6gica Venezuelica (see the bibli-
limiting factor, while humidity is sufficiently avail- ography in Roth
1981).