46 



{c) Sand Surfaces. — Here, again, we liave mallee scrub, witli 

 :an undergrowth of tlie Festitca irrifans (" Porcupine-grass" or 

 -spinifex), Asters, and Zygophyllum, spp. ; and where the sand 

 is not too deep forests of CaUitris verrucosa prevail. On the 

 ■edge of the sand ridges a profusion of herbaceous species grow 

 after copious rains, including several Swainsonias, Myrioce- 

 phalus Stuartii, Helipteruin polygalifolium, H. moschatum, 

 Crinum pedunculatum, Ophioglossum vulgatum. 



Expla:n^ations to Plate III. 



Tig. 1. Sketch-map of the Geology about the G-orge of the 

 River Murray from the Boundary to Blanchetown (based 

 on Mr. Pollitzer's chart). 



~Big. 2. Diagrammatic Section across the Gorge of the Lower 

 Section of the Eiver. 



