Allow me to quote from the "Cecil" link on the page you provided:
"Cecil has a classless object model. Objects have methods attached
directly to them, without needing a separate
    class to hold their format & behavior. One-of-a-kind objects with
their own behavior (e.g. true, false, nil, and other enumerated
constants) are easy to define."
also it is a, "simple prototype-based Object Model", which is at least
the same terminology that Self uses.

"subclasses" are only mentioned once, with the quotes.

But thank you for the link, I wasn't aware of Cecil's existence and
Vortex in particular looks fascinating.  You have given me my, "new
language fix" for the week. :)

"Chr. Rippel" wrote:
> 
> "Alexander Schofield" <pcs3 / mailhost.njit.edu> wrote in
> ...
> > Here here.  After reading about Self
> > http://research.sun.com/self/language.html a while back I am in full
> > agreement.  No classes at all.  The interesting thing about Self is that
> > it could easily simulate any class-based OO lang (multiple or single
> > inheritence, or some other type of mixin facility) without much of a
> ...
> 
> Hm, one of the self team member Craig Chambers later became team leader
> of the Cecil project http://www.cs.washington.edu/research/projects/cecil/
> - a very advanced OO-language and which is extremely  class  oriented -
> kind of interesting isn't it ...
> 
> /Christoph

-- 
Alexander Schofield