From: Kevin Thiele kevin.thiele@PI.CSIRO.AU To: TDWG-SDD@USOBI.ORG

The basic unit (atom) of a description is a statement of the form "For item x, element y has Value z"

In DELTA, character values in a description can't be separated from the 'attribute' which contains them, without losing information. This is because the order of the values, and the words 'or', 'and', and 'to' which may connect them, are significant. Also, the position of a qualifier (before or after a value) may be significant, and some qualifiers, e.g. 'reliability', may apply to the attribute as a whole rather than to a particular value.

Example:

5,3/3&1<when infected with virus>/<occasionally>2<@reliability 3>

= Flowers red, or red and white (when infected with virus), or occasionally yellow.

This doesn't seem to be accommodated in the proposal - at least, it's not spelled out.

--

Mike Dallwitz

CSIRO Entomology, GPO Box 1700, Canberra ACT 2601, Australia Phone: +61 2 6246 4075 Fax: +61 2 6246 4000 Email: md@ento.csiro.au Internet: biodiversity.uno.edu/delta/