344 A. A. HAMILTON. 



a similar northerly boundary, extends to Victoria, and P. 

 microphylla is found in all the Australian States. 



Two Oyperaceous plants with a limited distribution, 

 Tricostitlaria pauciflora Benth., low and spreading, and 

 Cyathochcete clianclra Nees., a tall graceful herb, each with 

 a small representation, and numerous tufts of the Tall Oat- 

 grass, Anisopogon avenaceus R. Br., are scattered among 

 the frontal rock benches and ascend the hillside. 



In a small swampy basin an association of aquatic herbs 

 is located. The succulent Spurrey, Spergularla rubra 

 Oamb., whicli covers large tracts of the tide-flooded marshes 

 at Cook's River, and the close-carpeted mud-creeper 

 Hydrocotyle asiatica L., occupy positions on its margin. 

 The tufted, slender, Triglochin striata Ruiz and Pa v., 

 ventures into deeper water, and its more robust congener 

 T. procera R. Br., finds in the centre of the basin a habitat 

 suited to its requirements. The three first named occupants 

 of the basin are cosmopolitan, but T. procera is confined to 

 Australia. A coastal form of the polymorphous Plantagd 

 varia R. Br., with succulent leaves and enlarged rootstock, 

 frequents the crevices on the escarpment flanking the 

 northern end of the beach at Maroubra Bay. 



On the strand below, an exclusive colony of the semi- 

 aquatic Cotula coronopifolia L., occupies a level tract near 

 the drainage channel. Several isolated plants of the Varie- 

 gated Thistle, Silybum marianum Gaertn., are the sole 

 occupantsof a wind-swept flat behind the dune embankment, 

 their long stout taproots, bared in extreme cases a foot 

 deep, supplying sufficient nourishment and support to enable 

 them to persist until the drift again sets in their direction. 

 The frontal slope of the embankment is dominated by the 

 Spinifex, which spreads over the ridges and into the wind- 

 blown channels, consolidating the* long stretch of uneven 

 slope between the crest of the embankment and the strand. 



