This came up in several different forms already, but any hierarchy should be able to be terminated at any level without generating a syntax error. Semantics need to be defined based on the depth of the hierarchy in any particular instance. This will help to accommodate the large body of semi-structured text descriptions that already exist and were discussed earlier. For example, the "Leaf" node might be defined to contain a list of optional properties (or sub-nodes) such as size, shape... but the standard should allow for free text description as well, perhaps by allowing for a <NaturalLangage> as one of the options, sort of an "other" category but with definable semantics.

One of the things that I did when I was coding up my original DELTA dataset (since I was wortking from published floras, etc) was to code a text character at the end of the characters for a given organ (e.g., leaf) that included the text of the protolog, or whatever textual description that I was working from . This wasn't necessarily for searching or information retrieval; but rather it was to allow me to *later* come back and verify the data without having to go did the original source off the shelf. Lazy woman's option.

Susan Farmer sfarmer@goldsword.com Botany Department, University of Tennessee http://www.goldsword.com/sfarmer/Trillium