1 12 Sutton, A Sketch oj the Keilor Plains Flora. [y^'x'xxYil 



A SKETCH OF THE KEILOR PLAINS FLORA. 



By C. S. Sutton, M.B., B.S. 



^Rcad before the Field Naturalists' Club oj Victoria, i \th Sept., 1916.) 



In attempting to sketch in an ecologic way the vegetation of 

 the environs of Melbourne, a commencement might perhaps 

 have been made more fittingly with that of the basalt plains, 

 seeing it is apparently the youngest of the three plant forma- 

 tions of the district. That the formation of the coastal sands, 

 already described as the " Sandringham flora," was first dealt 

 with was due, apart from its superior floristic attractiveness, 

 mainly to the fact that a knowledge of its plants, because of 

 the nearness and accessibility of the site, was more easily 

 acquired. Also it was feared that this flora was in such 

 imminent danger of destruction near by that very soon it 

 would not be so conveniently available for study. 



The flora of the basalt, however, has suffered even more 

 than that of the " sands " from haman interference. The area 

 is not favoured for residential purposes, and has not been much 

 built over ; but it has been put so thoroughly to pastoral and 

 agricultural uses that hardly any part now remains in the 

 virgin state. Sufficient of the original flora, nevertheless, in spite 

 of periodical burns, yet exists within the railway reserves, in 

 the stony paddocks which have never yet been cultivated, and 

 more particularly in the canyon-like water-courses and on their 

 steep banks, that a very good idea can be formed of its original 

 appearance and constitution. 



In this paper the area considered lies roughly within a circle 

 having a radius of about thirty miles from ^lelbourne, and 

 measures nearly 900 square miles. The continuitj^ of the 

 basalt is here broken only by the granite near Broadmeadows, 

 by a tongue of the Silurian to the west of Beveridge through 

 which the main ]:)ranch of the Saltwater River runs, and by 

 Ordovician rocks to the north and west of Sunbury, the same 

 rocks also overlapping the line discontinuously from near 

 Bolinda to Parwan. In the deeper water-courses the bed-rock 

 is also frequently exposed. On the western side the boundary 

 is defined by the Djerriwarrh Creek. To the south-west, where 

 the basalt is continuous with that of the Western District plains 

 extending to the Glenelg River, the limit set just touches the 

 eastern border of the granite of the You Yangs, and reaches 

 the shores of Port Phillip somewhat north of Point Wilson. 

 On the east the meeting with the Silurian is marked roughly 

 in succession by the Moonee Ponds and Darebin Creeks and 

 the Plenty River to near Yan Yean. Thence the line of contact 

 runs north-west to the Merri Creek near Wallan, and then to 

 the gap in the main divide at Pretty Sally's Hill known as 



