Daily Archives: June 13, 2011

ctenophore

We have established, in my note on amphithect, that, as the 1888 Encyclopedia Britannica says, “ctenophores furnish examples of eight-sided emphithect pyramids.” We now know that this means the pyramids are oblong but are symmetrical on two axes. But apparently not everyone knows what ctenophore signifies.

First off, I must affirm that that is the correct spelling. No matter how much your eyes (or your brain) may want it to be so, centophore is incorrect. These things don’t bear hundreds; gracious, that would be macaronic. The phore is from Greek φέρω phero “carry”, and cent is a Latin root. Nope, we want the Greek root χτένα khtena, which came by way of Latin spelling to be cteno here. You could connect it with amphithect by overlap to make a portmanteau, amphithectenophore (not that anyone does). There certainly is something gluey about that ct, anyway – it suggests a tip-and-back coarticulation on the tongue, very sticky (of course, in real life Anglophones simplify the onset).

It stands to reason that, not being Latin in origin, cteno also does not relate to catena, “chain”. Nope, χτένα is “comb”.

So… does that mean your hairdresser is a ctenophore? Hmm, well, I hope not, not in the sense it’s used in English. Actually, the combs of ctenophores are more hair than comb – they are cilia, rows of hair used to propel the squishy beasties.

Yes! Ctenophores are squishy little sea critters (a jelly body with two layers of cells holding it all in) that come in a variety of shapes, amphithect pyramid being but one. Most of them have rows of cilia. They have not brains but nerve nets. And yet they’re not at the bottom of the food chain, either – they eat all sorts of things, even each other, and can eat up to ten times their own mass in a day. They typically catch their prey using glue. (Perhaps they gum them up by asking them to say ctenophore.) Some are a few millimetres wide. Some are up to 1.5 metres wide.

Boy, that really stops the conversation, doesn’t it? A jelly-like thing, reminiscent of some protozoan viewed under a microscope, but large enough to wrap around a child. So, uh, how is it that they’re not much heard of?

That ugly name might have something to do with it. But of course there are various kinds, such as the cydippids and the lobates, and the ctenophores are known more colloquially as comb jellyfish. No, though, they’re not actually jellyfish – real jellyfish are cnidarians.

Yup. Cnidarians. There is it again, that c attaching to the beginning like some sucking (perhaps squishy) sea critter. I’m just gonna have to say that it’s what you get – they’re found under the c.

amphithect

On page 844 of volume 16 of the 1888 edition of the Encyclopedia Britannica, you will learn that ctenophores furnish examples of eight-sided amphithect pyramids. On reading this, you will of course think “Amphithect?”

You might from there go to a dictionary. If you do, hard luck for you: it’s not even in the Oxford English Dictionary. You might try to guess the meaning; the amphi will lead you to imagine it has to do with double-sidedness or something similar. But what about the thect? What the heck is that? Does it relate to tect as in architect? Nope. And good luck finding it in your handy little Pocket Oxford Classical Greek Dictionary.

You may find yourself down for the count or at least out of the court (the ct), just saying the word again and again, bouncing as it does across the various enunciatory positions – two lips /m/, lips and teeth /f/, tongue and teeth /θ/, back of tongue /k/, and finally tip of tongue on alveolar ridge /t/. Say it repeatedly and you make a neat circuit of your mouth. Pluralize it – amphithects – to get an extra fricative just to lubricate it further.

You can also play with the letters. Amp, hit, he; am, phi, the… match the pi, ham pith etc., at the chimp, hm – pathetic…

And while you’re doing that, perhaps your eyes will coast up the page a bit (page 844, remember? column 1) and see this:

In the highest and most complicated group, the Heterostaura, the basal polygon is no longer regular but amphithect (αμιθηκτος = double-edged). Such a polygon has an even number of sides, and can be divided into symmetrical halves by each of two places intersecting at right angles in the middle point, and thus dividing the whole figure into four congruent polygons.

An amphithect pyramid is thus one that has, for instance, a rhombus as its base. Which you would have learned earlier if you hadn’t gotten on the wrong bus, so to speak. But no wonder it was all Greek…

What? Ctenophores? Oh, yes, I’ll get to those next.