Happiness is a Warm Gun

 

The FEI Quanta 200F Environmental Scanning Electron Microscope

Two days ago, I took a select 16 specimens down to the UO Microanalytical Facility for ten cumulative hours of relentless, high-energy bombardment inside a scanning electron microscope. Having only ever worked on traditional compound microscopes, I needed a training session before getting started on my samples. At 10AM on Monday, I met with John Donovan, the facility director, who ran me through the relatively simple ins and outs of specimen prep, tray loading and software operation. Unlike compound microscopes, these machines cost hundreds of thousands of dollars, even second-hand ones, and while they are somewhat "difficult to break," to quote John, a lot is on the line. Close attention was paid and great care was taken.

 

UO Microanalytical Facility director, John Donovan, at the sample prep station

For this paricular SEM method, samples need only be placed onto double-sided carbon stickers, which are affixed to metal pegs, which fit neatly into a numbered carousel, 16 at a time. Other methods involve sputter coating samples with gold, or the use of osmium tetroxide, which I was grateful to have avoided. Both are more time consuming and destructive to the sample, and the latter is highly toxic.

 

The SEM specimen carousel, ready for zapping

The next 48 hours gave me an entirely new perspective on kingdom fungi. SEM images of all manner of things, organismal and otherwise, can be found throughout the web and the world, and it's not uncommon to see scanning electron micrographs (SEM photography) accompany mycological publications, but to be in the driver's seat of such a machine is a uniquely romantic experience. In light microscopy, harnessing the third dimension requires a combination of finesse and imagination, since the tissue is pressed between the flat glass planes of cover slip and slide. On an SEM, however, the user flies through an electrified vacuum from a computer cockpit, over and around and into the topography of the sample, as though it were a planet in space.

 

The septate and helically ridged spores of an as of yet unknown pin lichen (RLC1211)

 

The ostiolar mouth of an unknown parasitic fungus, occurring on the fertile surfaces of an 'encoelioid' discomycete (RLC1466) -- the Sarlacc is real!

 

An M.C. Escher-worthy mound of sleepy, spiraling, Hobsonia mirabilis spores ( RLC1276 ), the same as those featured in the first lab note

 

A slender school of spores from a Xylaria parasite we believe to be Hypocreopsis xylariicola ( RLC1340B )

These and many more wonders were beheld, micrographs of which will soon adorn their accompanying Mushroom Observer pages. The information gleaned from this richly detailed view of our material has already answered some questions and solved some mysteries which the light microscope could not.

Thanks to John and the entire UO Microanalytics Facility for giving me a friendly and comprehensive introduction to this truly spectacular instrument. I'm confident this is only the first of many sessions I will spend astronauting around the surface of these extraordinary organisms.