Quantifying the effects of weeds on biodiversity: beyond Blind Freddy's test.

An apparatus creates a three-dimensional picture by selectively positioning a single lenticular sheet over a number of figure sheets having linear form three-dimensional figures thereon. The figure sheets are positioned on a baseplate. A frame member is hinged to said baseplate and has positioned therein the lenticular sheet. The frame member pivots around the baseplate until the lenticular sheet overlies the figure sheet. Alignment means ensure the proper alignment of the figure sheet and the lenticular sheet. Resilient means may be provided to urge the figure sheet against the lenticular sheet.