Student list question

[elirtai]

No: HPFGUIDX 36359

Hello again,

This isn't strictly canon, although it may be related. Anyway
I think I'm still in newbie moderated status, so I guess it
will be rejected if it isn't fit for the list. So here it goes,
and sorry if this is not the place for it.

I assume most of you have seen JKR's drawings of HP characters
(if you haven't, they're on http://www.fictionalley.org/harryandme/).
They're rather good, by the way. I haven't found any references
to them in the list archives or the FAQs, I hope I didn't miss
anything.

My question is about the 'school list' drawings and how they
relate to the books. We get to see part of the student list.
For every name we see the house they were to be sorted into,
and two symbols. The first symbol is either a black square or
a white circle. The second one is a letter N in a box, a plain
Star of David, or a circle-enclosed Star of David.

I haven't found any relationship between these symbols and
the actual characters. Here's the list; does anyone know what
these mean?

Symbols:
  O  =White circle
  X  =Black square
 [N] =letter N in a box
  D  =Star of David
 (D) =Same, enclosed in a circle
 H,G,R,S = Hufflepuff, Gryffindor, Ravenclaw, Slytherin
           (Gryffindor usually appears enclosed in a circle)

The question marks mean the original is unreadable.

Name                    Symbol       Symbol         House

Abbott, Hannah          O           [N]            H
Bones, Susan            O            D             H
Boot, Trevor (*)        X           [N]            R
Brocklehurst, Mandy     O            D             R
Brown, Lavender         O           (D)           (G)
Bulstrode, Millicent    O            D             S
Corner?, Michael        X            D             H
Cornfoot?, Stephen      X           (D)            R
Crabbe, Vincent         X           (D)            S
Davis, Tracey           O            D             S
Entwhistle, Kevin       X           [N]            R
Finch-Fletchley, Justin X           [N]            H
Finnigan, Seamus        X           (D)           (G)
Goldstein, Anthony      X            D             H
Goyle, Gregory          X           (D)            S
Granger, Hermione       O           [N]           (G)
Graingrass?, Amelie?    O           (D)            S
Hopkins, Wayne          X            D             H
Jones, Megan            O            D             H
Li, Su                  O            D             R
Longbottom, Neville  ???????????? (**)
McDougal, Isabel (***)  O           (D)            R

*    In the books he became Terry Boot.
**   Neville's entry is not only hard to read, it has no symbols or 
     house at all (a last minute character maybe).
***  In the books she became Morag McDougal

Any ideas?

Cheers
Elirtai