ARID PORTIONS OF SOUTH AUSTRALIA. 



57 



GENERAL FEATURES OF FLORA OF SOUTH AUSTR ALIA. 

 THE NORTHERN PORTION OF SOUTH AUSTRALIA. 



The flora of the ^^rlihfi^" PP^^'^.flfi, S^vAiuLU"!:^^'^^" ^^ ^ marked 

 xerophy tic stamp. As much, however, can be said for most of the 

 perennials, if not all, in other portions of the state having a much 

 larger rainfall. As Taylor remarks, possibly with another idea in mind, 

 "it differs in degree according to the rainfall, but not in kind" (1918:89). 

 This is possibly the most remarkable feature of the vegetation of this in- 

 tensely dry region. That is to say, there are possibly no perennial forms 

 peculiar to it as such — for example, as the d ifferent types of succulents 

 de veloped in .other ar id and semi-arid regions, or ppssiBly ifl^xegions 

 whi^hjije desCTti a^~T^!^'lte species. 



In ^ oiEE* dr y ^ res^ion s some of the species aie^,jdecidaiaus^.- For 

 example, the fl.nfl,m'fl,s nf . t^ft ,SailM^^i^_ /^^ well as thqae-of the south- 

 western United Sta tes, have^foliage, which falls away with the seasons; 

 'and in the arid souiiwestern part of the latter country a species 

 (Fovquieria splendens) occurs which is deciduous with respect to the 

 occurrence of the rains, losing and forming the foliage perhaps several 

 times during the year, in a manner directly connected with the rains 

 aaid the intervening dry spells. Therefore, there may be possible 

 not a little variation in plants in extremely arid regions. Thus, 

 although the perennial flora of the far north has apparently little or 

 no striking peculiarities which set it apart from that of the regions of 

 South Australia more highly favored with rainfall, there is still not a 

 little diversity in it. 



Among tlip Tjinst.JptfirestiTi ^ trees- oLiha. dry r^io n are se veral 

 BBficifis uof Aoa cda-^f^aMi show important morpEologicaI7°as weff as 



aysiological, differencesT"* Certain of the hakeas exhibit remarkable 

 differences as between species and marked adjustment to an arid 

 environment. Of -LTip ^h^^^", tlinsp nf the g enus Eremophila are of 

 especial interest. Out of the B9 speOlws, including those now put 

 under Pholidia, Tate gives 17 species as occurring in the northern 

 portion of the state. Of the shrubs, this is the desert plant par 

 excellence. But the halophytes of whatever specips. ,SQlistitute the 

 most promin i ffpt filement of the flbraort his region . Tat£,„gixesj54 

 gEg cies ofThe r/henopodiacea B aiiH AumaTSnfacese from the far north, 

 most of which are highly^^aT t I ' m siu lj a n L— .T I i ui'l ' n f&-a-4e w &-sue eu lent 

 annuals, or half shrubs. AmongTlieS5~are species of the Zygophyl- 

 laceae and Calandrinia balonnensis (Portulacese) ; the latter bears large, 

 succulent leaves and is much sought after by animals. Stuart's pea, 

 Clianthus dampieri, is one of the most showy of the annuals. 



Of the grasses, among the most frequently met are the "bunch" 

 forms, as Triodia irritans and Spinifex paradoxus, which are widely 

 distributed in the interior of the continent. In addition, according to 



