Thursday, April 12, 2018

How Do You Spell That?



Day 181: If you hang around any gathering of lichenologists long enough, you'll hear somebody mention the "pee test." You'll have misspelled that mentally, I guarantee it. What they are talking about has nothing to do with urine. The "P test" of lichenology uses p-phenylenediamine to see if a specimen contains certain reactive lichen substances. P is generally only available in large, pricey quantities which put it out of reach for most amateurs, but fortunately, one of the professionals at the Northwest Lichenologists conference had it made up in small, affordable bottles. She referred to it as "a lifetime supply"; it only takes a few grains of P dissolved in ethanol to make a drop or two of solution, but the solution has a shelf life of two days at most. Then it should be discarded and freshly made. Since only a small amount is needed, the best container for the job is a 0.2 ml disposable centrifuge tube, something else which is only available in sizeable quantities. Ever wonder what 1000 0.2 ml centrifuge tubes look like? I didn't actually count them, but that's what the package said. I can P whenever I want now!

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