Sunday, February 10, 2013

Brachycythere ~ Learning the Lexicon

            King.  Let’s further think of this,
Weigh what convenience both of time and means
May fit us to our shape.  If this should fail,
And that our drift look through our bad performance,
‘Twere better not assayed.  Therefore this project
Should have a back or second, that might hold
If this did blast in proof. . . . .
Hamlet, Act IV, Scene VII

At present, I am struggling with two kinds of texts.  The first is Hamlet.  In the passage given above, the King plots with Laertes to fashion a fencing match, replete with a sharp rapier and poison, sure to lead to Hamlet’s death.  Though I know the context, I wasn’t quite sure of what the King is advising.  Fortunately, in my Folger Library edition of the play, each page of dialogue has a facing page with annotations, explaining obscure words or passages.

May fit us to our shape means “may suit our design.”
Drift is “intention” (ah, as in “catch my drift”).
Blast in proof, a great phrase, means to “fail in the trial.”

And, so, I draw from this passage (which in the final analysis really wasn’t so obscure) the following – Claudius, the King, almost thinking aloud, advises that they should seize the opportunity to carry out their plot when it presents itself, but should it not and their plan go bust, they need a backup.  [Later edit:  The King, I think, worries that they wont be able to carry off their ruse convincingly - "our drift look through our bad performance."]

In reading Hamlet once again, I am amazed, as always, at how the play speaks to me some four centuries after it was written.  Hamlet’s struggle to deal with his grief and to act decisively, to do what he believe he must (or is expected to do), given the dire knowledge he has discovered, still resonates all these years later.  Admittedly, reading Shakespeare requires some acclimating.  I have to slow down, pay closer attention to the words, and use the annotations.  At times, I think, “Yes, that certainly looks and sounds like English, but I’ll be damned if I can make any sense of it.”  The work to draw out the meaning is a small price to pay for admission to this great play.

Coincidentally, I have also recently immersed myself in the paleontological literature on Brachycythere ostracodes.  Species from this genus of minute crustacean can be found as far back as the Cenomanian Stage (99.6 to 93.6 million years ago) of the Upper Cretaceous Period.  The genus went extinct early in the Oligocene Epoch (33.9 to 23.03 million years ago).  (Terry Markham Puckett, Systematics and Paleobiogeography of Brachycytherine Ostracoda, Micropaleontology, Volume 48, Supplement 2, 2002.)

I am trying to develop some ability to distinguish among the shells of late Cretaceous Brachycythere species.  As modest a goal as that may sound, it’s really quite a daunting challenge because the differences among Brachycythere species are, at least to my eyes, deucedly subtle.  Still, those distinctions aren’t the focus of this post.  Rather, it’s the learning of the language used by paleontologists to describe the general features of these ostracodes, a language replete with words that are obscure (to this layperson), even as they sometimes turn out to be singularly efficient, and, once in awhile, resoundingly poetic.

Reading Shakespeare and reading descriptions of ostracode fossil species are curiously analogous activities.  Certainly, these paleontologists aren’t Shakespeare and the importance of their writing pales beside that of the Bard, but the process of reading them is similar – I have to recognize that, for all of the strangeness of some passages (“sure looks like English”), I can unpack the words, grasp some meaning, and make sense of it.  But I wish the ostracode literature had the facing pages of annotations explaining the really obscure stuff.

Here’s an example of the opaque paleontological texts through which I’ve been working.  What follows is an excerpt of a description of the Brachycythere nausiformis by Frederick M. Swain (Ostracoda From Wells in North Carolina:  Part 2.  Mesozoic Ostracoda, U.S. Geological Survey Professional Paper 234-B, 1952).  This is a new species which Swain was naming and describing here.

Shell subtriangular to subovate-acuminate in lateral view; greatest height a little more than one-third from anterior end; dorsal margin strongly arched, long posterior slope truncated and slightly concave; ventral margin gently to moderately convex; anterior margin broadly rounded, bearing tiny denticulations on each valve in well preserved specimens; posterior margin acuminate, strongly extended medially, truncate and slightly concave above.

. . .  Median surface of valves strongly convex with ventrum swollen to produce short alate expansions, and projecting beyond ventral contact of valves; crest of each ala bears a low longitudinal ridge with a broad furrow about it; a second weak longitudinal ridge lies dorsal of furrow.  A prominent elongate eye tubercle lies at anterodorsal angle; ventrad of tubercle in right valve is a short oblique sulcus, corresponding feature in left valve is deeper, wider and more pit-like. . . .

Best to have a specimen at hand to have the slightest chance of making any sense of this description.  Here’s my rough line drawing of a B. nausiformis (based on an actual specimen) in which I’ve tried to accentuate a few of the key features Swain described.  Each ostracode lives within two shells that are hinged at the top; the shell depicted below is a right valve.  The scale line is 200 microns (equal to 0.2 millimeters) which means this specimen is about 0.8 millimeters long.

And here’s my rough translation of Swain’s description:

Seen from the side, the shell is somewhat triangular to nearly egg shaped with tapering ends.  Its tallest point is a third of the way from the front where the top margin is strongly convex.  From that highest point, the top margin slopes to the rear end where it stops abruptly with a slight dip and a tapered end.  The bottom margin is somewhat convex.  The front end of the shell is broadly rounded, sometimes showing fine notches or teeth.

. . . The middle expanse of each shell is swollen, bowing out strongly, particularly toward the bottom.  Each swelling drops below the bottom margin where the two valves meet.  A ridge tops each of these swellings and is set off by a wide furrow (a faint second ridge parallels the first).  This creates wing-like projections from these ridges.  A prominent eye spot appears at the top peak toward the front of the shell.  In a right valve, a short groove runs below the eye spot; in a left valve, this groove is deeper, more pit-like. . . .

Some sense emerges from my version, I think.  I have arrayed this detailed description against several others that I’ve gathered which identify key characteristics of this and other Brachycythere species.  Slowly, I am coming to learn about a few of the key differences that others have posited distinguish among these species.  (Fortunately, I have an expert to whom I can turn when things gets problematic.)

In this process, I’m compiling a list of new words (well, nearly all new to me).  Given the general shape of the Brachycythere ostracodes – all of the species bear some close resemblance to the outline depicted above – several of these words are wonderfully apt.  Here’s the list at this juncture (these definitions are somewhat massaged versions of those given in The New Oxford American Dictionary, ebook, 2008):

  • acuminate = tapering to a slender point
  • alate = having wings or wing-like projections
  • carina = structure shaped like a keel (carinae, plural)
  • fusiform = tapering at both ends
  • punctate = having small holes or pits
  • subtriangular, subovoid = honestly, I didn’t know that the prefix sub in these instances means that the object being described by these adjectives is not precisely or perfectly triangular or egg-shaped
  • sulcus = groove or furrow
  • tubercle = nodule or projection
  • umbo = rounded elevation, like the boss of a shield (in shells, the umbo is the area above the hinge as described in a previous post).
In the midst of all of the often long winded descriptions I’ve been reading, a few stand out for their conciseness and their brevity (perhaps limiting their paleontological utility).  A couple even offer, dare I say it, a touch of poetry.  The following description of Cytheropteron sp. A (now known as Brachycythere ovata) was written by Merle C. Israelsky, and was originally published as a continuous paragraph (Upper Cretaceous Ostracoda of Arkansas, Arkansas Geological Survey, 1929):

Viewed from the side, subovoid;
higher before than behind.
Viewed from above or below,
outline is broadly fusiform,
slightly attenuated
before and behind;
valve contact
sinuous dorsally,
but slightly
sinuous ventrally.

Okay, I’ll concede that perhaps I’ve read too many of these.

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