From ‘Archive 1996 – what were we up to 20 years ago?’, the Spring 1986 meeting item ‘Genus Index’.


The RBG Genus Index is a database of genus names showing their validity and relation to other genus names, and the family they are in, all as perceived by RBG. It is written in COBOL end uses two Indexed files, one for the Families and one for the Genera. It is called by typing SGFN 1. Why have a Genus Index? Genera may be created or deleted by botanists anywhere in the world as long as they publish the fact according to a set of international rules for botanical nomenclature (which are not, however, enforceable). This system has lead to much confusion, and it has been realised for many years that a codification of genus names is needed.

2. How is the Index structured?

Genus names are seen by the program as being a collection of hierarchies, each one headed by a name accepted by RBG as being valid both nomenclaturally and taxonomically, and filled out with the various categories of known synonyms (other names describing the same plants). The hierarchical structure of one ‘name tree’ is as below;
Available synonyms may be used; they have been validly published but represent only a part of a genus accepted by RBG. Unavailable synonyms and spelling variants may not be used. The former may be invalidly published, superfluous (true synonyms) or homonymous (the same name used twice) Each record on the genus file has two keys to accomplish the chaining above. The first contains a value unique to each record. The second contains the value of the record to which it chains. This allows the program to trace up or down chains very easily. A third key links each record with a family name from the family file.

3. Uses of the Genus Index file.

Any botanist, from any terminal, can see almost instantly RBG’s view of a genus name they might be using. In addition, the indexed files can be linked to any other system on the RBG computer, allowing, for example, validation of genus names and automatic allocation of family name.