There is little or no sense of intraspecific variability
and extremely little synthesis. Keys are provided for the up
to a dozen species in the larger families, but these wouldn't
be particularly useful for identification, even elsewhere in Venezuela.
Each of these families has many more species in northeastern
South America and 1000-10,000 species worldwide. For the
physiological ecologist, we have the already established observation,
without quantitative testing, that venation gets denser and more
compact as leaves get smaller with increasing stature in the forest.
This applies, as well, to juveniles of canopy species, which
also have less organized venation than adults of the same species.
Except for some casual citations in the introductory parts, there is virtually no acknowledgment of the extensive literature on leaf venation, particularly the rich paleobotanical and paleobotanically inspired literature. There isn't even any meaningful cross-referencing of the author's other books on the same trees. All told, then, this in not Prof. Roth's most interesting book.
It is easy to think of different approaches to the
material that would have been far more useful and had a bigger
impact than the approach taken here. Since more than 65,000 trees
were felled for the original sample, there was a real opportunity
to assess patterns of intraspecific variability, a potential problem
that has never been dealt with in depth. Alternatively, Roth
might have taken a more ecological tack and covered the broad
range of environments in Venezuela that she has investigated over
the years, with a serious attempt to test for environmental correlates
of fine venation patterns. Finally, selecting a single family,
or a few families, for more detailed comparative study would also
have more clearly matched the title of this book than its actual
contents. - James E. Eckenwalder, Department of Botany, University of Toronto.