Question about Naked Ladies

J.E. Shields
Fri, 21 Dec 2007 05:18:41 PST

One expression for this that I recall is Rassenkreis, a breeding or racial 
circle or arc.  I think I have seen "cline" applied to the sort of 
variational gradient you describe.  We still someone who knows for sure to 
enlighten us!

Jim Shields

At 07:04 PM 12/20/2007 -0800, David wrote:
>There is a botanical word I'm looking for ­ it's something like gradient, 
>but I don't think that's the word.  It is used when referring to a species 
>with a broad distribution which has one form at one end of its 
>distribution and a very different form at the other end.  The two extreme 
>forms are sometimes considered separate species.  But when the 
>distribution is continuous and every intermediate form is found and there 
>is no bar to interbreeding, this special word is used, and the population 
>is considered a single species with disparate extreme forms

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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