A revision of the genus Digitaria Haller (Paniceae: Poaceae) in Australia.

The DELTA computer system is used in the presentation of a revision of the genus Digitaria in Australia. Thirty-eight species are recognized, new species being D. imbricata, D. lanceolata, D. minima and D. oraria. Methods used in the production of the computerized taxonomic output are described. Characters used in the keys and descriptions are discussed and where necessary illustrated by scanning electron microscopy and light microscopy. Species are grouped into sections and a key is given to these categories. Section descriptions are listed in alphabetic order. Two keys for the species are given. The first is a standard morphological key and the second is based entirely on vegetative and anatomical characters. Species descriptions are listed in alphabetical order. It is concluded that the DELTA system provides an efficient means of accumulating, storing, editing, manipulating and presenting classical taxonomic data.