Image 1: A single grain of pollen as a black, roundish object on the left side of the view.

Image 2: Multiple grains of pollen as black, amorphous objects on the top and bottom of the view.

The sample was obtained just south of the Caltech Turtle Pond (274 Olive Walk, Pasadena, CA 91125, see image below) at 4:10pm, May 10, 2019. Two flowers were picked and sliced so the pollen could be removed and placed on a slide.

This is a jasmine plant with five white petals. The likely species is Jasminum officinale (see https://en.wikipedia.org/wiki/Jasminum_officinale ), though there are more than 200 species of jasmine.

Since the Foldscope uses a 2.38mm lens giving 140x magnification, the approximate size of the pollen grain in the first image is about 0.04 mm (or 40 microns) in size.

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