Re: About the angle of view

["Jaime A. Headden" <qilongia@yahoo.com>]

Sam Barnett wrote:

<In palaeo-pictures, terms are used such as lateral,
dorsal, antero-dorsal etc, to indicate the angle you
are viewing them, but no one ever gives a key as to
what they all mean.  Eventually one becomes familiar
with most, but there are a few holes in my current
repertoire I would like to fill:>

  I am to understand that, while going very broad in
this respect, and forgetting (momentarily) that Doc
Holtz here wrote a chapter in _Complete Dinosaur_ on
this subject (directionality in fossils), there are a
lot of rather "new" people that may find this info
helpful, so I will generalize and state the most
obvious directions and aspices thereupon.

  Basically, there's just a few simple things about
directionality in illustrations and photos, but they
can be quarrelsome to work with sometimes (Russian
science papers use three different ways to indicate
direction, and in one sentence, I found all three).
One thing is that these do not always indicate the
direction of view, but more particular and common they
represent the actual object in orientation.

anterior: towards the front; posterior is the reverse.

ventral: towards the bottom, or away from the bottom
of the vertebral central or main axis of the animal or
orbject; dorsal is the reverse.

lateral: towards the outside, or just the side; medial
is the reverse; also, mesial and lateral are paired,
but only when dealing with jaws and/or teeth.

labial: towards the lip or outside of the tooth or
jaw; lingual in the reverse, and is irrespective of
the prescence of a tongue.

rostral: in a skull, towards the front or the snout;
caudal or posterior is the reverse; likewise, cranial
and caudal are paired, and mean towards the head or to
the tail; in a tail, posterior and anterior, or the
next pair are used.

distal: towards the end (away from the origin) of the
object), proximal is the reverse.

sagittal: towards the midline of the animal, or
parallel to the sagittal plane that divides symmetric
forms in half; lateral is the reverse.

plantar: towards the bottom of the foot or, as in
dinosaurs that walk on upright metatarsals, towards
the back of the foot, or "caudal" side; also use
flexor, menaing towards the direction the toes curl;
respectively, facial and extensor are the opposite.
Can use these for manus, limbs, etc.

  Pairs of terms indicate two or three dimensional
axes, as in anteroposterior (running front and back)
lateromedially (running middle to side) posteroventral
(running rear to bottom) labiolingual (lip to tongue)
etc.; anterolateral to posteromedial (running from the
front and outside to the back and inside); laterally
is a single term, and means either to the sides, or
from side to side, so is both one and two dimensional.

  Terms like "aspect" and "view" follow such terms to
give the reader and viewer an idea that they're
actually "looking" at something, not just a flat piece
of paper; in addition, the term "oblique" is used to
incate a figure shown in two faces, anterolateral,
posteroventral, etc., which most artists may be
familiar with. Illustrations in three aspices, which
may be used to show a feature that is otherwise not
apparent, can be labelled antero-lateroventral, or
similar construction which contains all three
directions shown.

  Hope this helps.
 

=====
Jaime "James" A. Headden

"Come the path that leads us to our fortune."

Qilong---is temporarily out of service.
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