371) 



ON THE MANGROVE AND SALTMARSH VEGETATION NEAR 



SYDNEY, NEW SOUTH WALES, WITH SPECIAL REFERENCE TO 



CABBAGE TREE CREEK, PORT HACKING. 



By Marjorie I. Collins^ B.Sc, Linnean Macleay Fellow of the Society in 



Botany. * 



(With Phites xxvi.-xxxii.; and eleven Text-figures.) 



The observations recoi<led in the following i)ai)er were commenced during 

 September (Spring) lUlti and continued with some interruptions until .Tune. 

 1021. 



It is the aim of the writer to give an account of the nature of the tidal ilats 

 and their vegetation, in the neighbourhood of Sydney, and more espe<nally, to 

 describe a series of changes wliicli have taken place, during the past five years, 

 at Cabbage Tree ('reek. Poi-t Hacking. 



The wi-itcr's thanks are due to Prot'essijr T. (i. B. Osborii, Ftiiversity "f 

 Adelaide, for uuich helpful discussiiju througliout the course of the work, and 

 to Mr. J. H. Maiden, F.R.S., Director of the Botanic Gardens, Sydney, who 

 kindly gave her a<'cess to the National Herbarium. To Mr. A. A. Hamilton, 

 the wi'iter is indebted Tor assistance in idciitilication of tlie vari<ius species 

 collected. 



PuVSr()(nUlMIK' FkATURKS ok TIIK CoA.ST >fKAR SVDN'KV. 



Tlie coastal strip in the neighbourliood of Sydney shows many leaturcs oT 

 marked physiographic interest. It is chai'acterised by striking, nuieh branched 

 inlets, in which, for (lie most l)art, deep water is found close up to the rocky 

 shores. Woolnough says of tlicse "... . tliey owe their existence to the sub- 

 raerg'ence of a partially dissected plateau"; also, ''At the close of the latest cycle 

 of erosion there was a general subsidence amounting to at least 400 feet in the 

 central portion of the area, [referring to the coa-st of New South Wales.] This 

 caused the 'drowning' of the valleys of the coa.stal rivers, and the conversion of 

 these drowned vallevs into nuignificent harlxiurs" (.lose, Taylor an<l Woolnough, 

 1011, p. 131). 



Port .Tackson, Botany Bay and Port Hacking, which couu' witliin (lie 

 scope of the present work, all represent drowned river valle>s with complex 

 outline (Text-fig. 1). The rocks outcropping on the shores of these inlets, and 



•This investigation was commenced in 1916 while the writer held a Science Eesearch 

 Scholarship in the University of Sydney. 



