MAPPING THE DISTRIBUTION OF PLANTS BY MACHINE

This paper describes the introduction of data-processing methods to the recording of data on the distribution of the vascular plants of Ontario. A programmatic typewriter is used to prepare the complete record for filing in the Catalogue and a by-product tape can be converted into a punched card. The punched card contains a code number for the name of the plant and X and Y co-ordinate readings for the geographic location of the record, together with other information. These cards are used to print distribution maps of the species by means of a tabulating machine or a digital plotter. Tests were carried out on three different machines. Tabulators are satisfactory to display records on a regular gridded pattern (as used in the Atlas of the British Flora), but digital plotters are required for the accurate plotting of exact localities on "dot maps" usually made by hand. Examples of various forms used in recording data and one distribution map plotted by an I.B.M. 407 Accounting Machine are illustrated.