Slug Radula

WalterD · Post by **WalterD** » Mon Oct 14, 2019 9:06 am

The tongue of a slug , or radula, is a classic microscopy object and relatively easy to obtain. I did not see it many times in this forum, but the posts showing the radula were mostly fascinating.

Because I may be a bit lazy (as a microscopist) I did not really go out to look for it, but yesterday it came to me. The slug was going its way in the parking lot under the appartment building where I live (I don't have a garden).
After killing and dissolving it in sodium hydroxide, the chitin tongue was all that remained. In particular interesting to observe with DIC.
For now it is kept in water, so not mounted yet. Fluorescence will be the next step for this tongue.

1 = 16x ("pseudo DIC, not dedicated objective) > Note : see my homepage for high resolution.
2/3 = 25x
4/5 = 40x

All with 1/4 lambda slider

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5.

Thanks for looking

Sumguy01 · Post by **Sumguy01** » Mon Oct 14, 2019 7:20 pm

Interesting.
Thanks for sharing.

houstontx · Post by **houstontx** » Mon Oct 14, 2019 9:20 pm

Nice photo set...but how does one find and separate the tongue from the dissolved sludge? Is it then neutralized? What is the concentration of NaOH solution?

WalterD · Post by **WalterD** » Tue Oct 15, 2019 1:29 pm

Good to hear that, Sumguy and Houston.

How to do that?

Nice photo set...but how does one find and separate the tongue from the dissolved sludge? Is it then neutralized? What is the concentration of NaOH solution?

The description says:
-let the slug move on a smooth surface.
-kill the slug fast and painless by cutting off the head.
-I put the head in a 01.N NaOH solution, that's 4 grams per liter so not too strong.
-The original recipe tells to boil it but au bain marie at about 50 Celcius or in an incubator for a couple of hours works fine.
-Rinse it in water. The tongue will clearly be the only remaining item in the solution, everything else is completely dissolved.
-After that it can be neutralized in vinegar or acetic acid solution, I did not do that.
I experimented a bit with fluorescence but not content with the present light distribution, a lamp better suitable for this microscope is en route fortunately.

(21x, inverted UV excitation)