Elodea Leaf Morphology

[John E. Silvius]

As many of you know, the leaves of the aquatic plant, Elodea, consist
of two layers of photosynthetic cells.   Can anyone explain the
derivation of these two layers during leaf development?    I assume
they are derived from ground meristem as opposed to protoderm.   If
this is correct, what happens to the original protoderm assuming it is
formed at all?     Perhaps someone can provide a journal article
citation featuring a study of leaf development in Elodea.    Thanks!

John E. Silvius, Ph.D.
Professor of Biology
251 N. Main St.
Cedarville University
Cedarville, Ohio   45314
E-mail:   silviusj at cedarville.edu 
http://www.cedarville.edu/dept/sm/silvius/index.htm
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