Define Epigeal and Hypogeal

J.E. Shields
Mon, 04 Jan 2010 11:51:09 PST
The problem with the simple definition -- cotyledons above ground after 
germination vs. cotyledons below ground -- is that for many monocots, the 
cotyledon stays inside the endosperm structure and that is where the seed 
was -- above ground or buried, happenstance perhaps -- when the seed 

So it appears that the usage for monocots may not work with the usage for 
dicots, and seeds don't work with ants.  Does Edward McRae's definition, 
presumably from the workers in the genus Lilium, fit all other monocots?

Here is my adaptation of McRae's definition of epigeal:

  "A pattern of rapid germination in which the seed quickly produces a 
cotyledon above ground followed soon by true leaves. The first bulb 
structure may only be formed much later in the first growing season."

Do some Lilium actually produce a true cotyledon?

I hope some more experts will contribute definitions.  I don't need to 
include the ants, but diverse plants need to be covered by definitions of 
the terms.  Can we even cover all geophytes with one simple pair of 
definitions of epigeal vs. hypogeal?

Jim Shields

At 02:20 PM 1/4/2010 -0500, you wrote:
>It seems to me that the answer to questions like these is the same as the
>answers to questions about grammar or taxonomy: there is no one, central,
>universally accepted authority for such things. Each field of endeavor
>(whether scientific or avocational) makes  and uses its own definitions.
>It's only when these fields intersect or overlap that problems arise. For
>instance, to use grammar as an example, isn't that why large organizations
>(such as newspapers and universities)  which publish a lot of material have
>style manuals?
>People who believe that there is always just one correct way to do things
>will be left scratching their heads or sharpening their knives. People who
>accept diversity will have the pleasure of discovering just how inventive
>other people can be.
>I'll be keenly following this thread to see where it takes us.
>Jim McKenney

Jim Shields             USDA Zone 5             Shields Gardens, Ltd.
P.O. Box 92              WWW:
Westfield, Indiana 46074, USA
Tel. ++1-317-867-3344     or      toll-free 1-866-449-3344 in USA

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