583 



ECOLOGICAL NOTES ON SOUTH AUSTRALIAN PLANTS. 



Part 1. 



By Ernest H. Ising. 



[Read October 19, 1922.] 



Plates XXXVIII. to XLII. 



I, Introduction. 



These notes are the result of a trip taken along the 

 Transcontinental Line between Hughes and Kingoonya from 

 September 5 to 24, 1920. Collections of plants were made at 

 the following places showing the number of miles from Port 

 Augusta: — Hughes, 567 miles; Ooldea, 427 miles; Imjnama, 

 407 miles; Barton, 376' miles; Wynbring, 321 miles; Tar- 

 coola, 257 miles; and Kingoonya, 209 miles. 



The rainfall over the area collected had been heavier that 

 year than for a number of years, resulting in splendid growth 

 of native vegetation. Seeds that were dormant for a 

 number of years must have germinated that year, for there 

 was. an abundance of plants at all the places visited. 



Reference will be made in this paper to the ecological 

 factors noted in connection with the plants seen and collected 

 at the various places mentioned. Plants w^ere collected up to 

 three miles from the centres referred to. 



Throughout the trip I was helped very considerably in 

 collecting and drying by Mr. A. M. Lea, F.E.S., Government 

 Entomologist, who was collecting insects for the Museum on 

 the same trip. 



An asterisk denotes an introduced plant. These were not 

 seen to any extent and only close to the railway stations. 



For assistance in identifying some of the specimens I am 

 indebted to Mr. J. H. Maiden, I.S.O., F.R.S., F.L.S., etc.. 

 Director Botanic Gardens, Sydney {Eucalyptus and Acacia) ^ 

 Mr. J. M. Black, and Professor T. G. B. Osborn, D.Sc. 



II. Physiography. 



1. the null arbor plain. 



Size. — The Nullarbor Plain commences at Ooldea at its 

 eastern boundary and stretohes away westward to the border 

 for 170 miles, and thence into Western Australia. Its 

 southern boundary is the coastline of the Bight, and it 

 extends for about 100 miles north. 



