The image shows a magnified view of a twig/shoot like structure. Notable features include the small fibers emerging from its surface (see the upper right), what appears to be lines running alone (horizontally) the sample, and the relatively smooth outline of the sample. It is dark colored partly because the sample is brown-ish but also because light only illuminates the exterior area of the sample.
The sample (right image below) was collected at 2:53 pm on 5/27/2019 at the California Institute of Technology, outside of Ruddock House (1320 San Pasqual St, Pasadena, CA 91106). It was taken from a pile of plant matter (left/middle images below). It was not attached to anything, so I was able to simply lift it from the pile.
The sample was then prepared by taking a small part of the twig/shoot and mounting it on a slide.
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