IIOKN EXPEDITION — BOTANY. 131 



Gmcra Exotic. r.piipra 



Sp. Sr. Emc-mic Distrilnitioii. 



Exotic. Endemic. t-'icK-'iiK- 



Spartotlianiiuis teucriifolius - - X Lowland, not uiicouiiiion. 



Spai'totlianiiius puljerulus - - X .Saxatilc, very rare. 



Carissa Browni - - X - Lowland and sa.xatile. 



Solanuni, spp. - - - - X - Lowland, wliolly or in [)art. 



Styphelia Mitchelli - - - - X Sa.xatile, very rare. 



The colonising power po.sse.sscd by the Ereuiian plants has had freer scope to 

 exercise itself in the unoccupied tract of the low levels on the reduction in si/e of 

 its lake-basins and water-ways than was possiljlc in the more stable e.xtcrnal 

 regions. Anotlier feature pointing in the sanies direction is tlie high state of 

 specific luxuriance in many of its exotic genera ; and that a process of differentia- 

 tion seems to be in progress, because of tlie local racial cliaracters exhibited in 

 some genera and species. Further, the many monotypic genera, which are for the 

 most part offsets from Australian types altered l)y new surroundings, show no 

 singularity which may Ije attributed to a high antiquity. 



An indispen.sable property of the Eremian plants is that of rapid germination, 

 so as to take advantage of the rare opportunities when tlie physical and hygro- 

 nietric conditions of the soil are favourable and ((uite irrespective of temperature. 

 Moreover, the long ch'oughts intervening between tlie favourable periods necessitate 

 another (|uality in tluiir seeds — that of resistance to long exposure. Individual 

 tenacity of life is another essential condition of maintaining a foothold in the dry 

 or desert zone. 



The balance of 21iS species in category TIL are either actually Autochthonian 

 or Euronotian, or are related species, and as a whole may be viewed either as 

 residues of a common Australian llora, or as modified descendants therefrom. 

 Here belong all the saxatile s])ecies of endemic genera, as also others of endemic 

 genera inhabiting the low-level tracts. 



The Larapintiiie area, in connnon with the rest of Australia, contains repre- 

 sentative genera of that primitive flora which marks the close of the Cretaceous 

 and the (;arly stages of the Tertiary peri(jd, as has been made known chi('lly by 

 the researches of Baron von Ettinghausen (C(jntributions Tertiary Flora of Aus- 

 tralia, Mem. Geol. Surv., N.S.W., Lsys). The forms belonging to this type of 

 vegetation, which are ijreseiit in the area, are Incus, Lora/ithus, Fittosponim, 

 SaiitaliDH and Cassia, in association with Callitris, Casuarina, Grevil/ca, I/akea, 

 Eucalyptus, and phyllodineous Acaciie, now restricted to Australia. Most of the 



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