st--in connection with a variety of
things. For example:

<P><U>Could there be a hierarchy of snowflakes</U>? Actually there could
be many such hierarchies: Presumably there is a probability spectrum for
different flake shapes; Formative mechanisms may be plural or subject to
complication or external influences, in which case either the causes or
their effects may canonically progress in chains and branch in--chronological
or nomological-- trees; Probability or existence of certain flake forms
may be a func