I'm looking for examples of flowers that, because of some morphological
change, provide physical evidence of having been visited.  Something more
conspicuous than the fact that nectar or pollen have been collected, or
pollen deposited on the stigma. For example, Calathea flowers that have to
be triggered in order to effect pollination.  I'd be interested in both
examples like this one, as well as others in which the morphological change
may be temporary; for example flowers in which the anthers are thigmotropic
and move in response to the probing of a pollinator but reset themselves
later (e.g., Stylidium, Kalmia, etc.).
Thanks.
 
        *****************************************************************
        *                                                               *
        *       David W. Inouye                 INTERNET address:       *
        *       Dept. of Zoology                  [log in to unmask]     *
        *       University of Maryland                                  *
        *       College Park, MD 20742          fax: 301-314-9566       *
        *       301-405-6946                                            *
	*								*
	*****************************************************************