64 PLANT HABITS AND HABITATS IN THE 



THE COPLEY ENVIRONMENT. 



PHYSIOGRAPHY. 



The topography and hence the plant habitats in the immediate neigh- 

 borhood of Copley are extremely varied, owing mainly to the relation 

 of the region to the Flinders Mountains. The main portion of the 

 north end of the Flinders lies to the east, between Copley and Lake 

 Fromme, but a lesser part is between the village and Lake Torrens 

 on the west. Copley is thus in the bifurcation of the range, with out- 

 lying hills and low mountains within one mile or more on either side. 

 The plain at Copley constitutes little more than a valley, but it widens 

 to the north, becomes lower in altitude, and soon constitutes a leading 

 feature of the topography. Copley lies between the 500-foot and 

 1,000-foot contours and hence is near the upper level of the Cretaceous 

 beds (Taylor, 1918:87). In the Flinders to the east are peaks which 

 are among the highest of the entire ranges, including Mount Serle, 

 the Freeling Heights (3,120 feet), and Mount Benbonyanthe (3,470 

 feet). The altitude of the division of the Flinders to the west of 

 Copley is 2,000 feet or less. The observations upon which the present 

 study is based were made within a 15-mile radius of Copley and were 

 confined to an altitudinal range of approximately 1,000 feet. Within 

 this small region, however, there is to be found a bewildering array of 

 hills, valleys, slopes, washes, and flats which would be beyond the pur- 

 poses of this study to describe accurately or in detail. The device 

 will be resorted to, however, of attempting a characterization, so 

 far as possible from the data at hand, of such of the habitats as appear 

 to be of most interest in connection with this study. 



The Flinders on either side of Copley are for the most part of the 

 Cambrian age, but there are also Mesozoic rocks. Thus the slate hills 

 with vertical strata to the east of the town are possibly of the former, 

 and the table mountain just southeast is of Mesozoic. The latter is 

 part of the desert sandstone previously seen at Oodnadatta and which 

 formerly extended over most of central and northern Australia (How- 

 chin and Gregory, 1909:93). Thus the underlying rocks, and conse- 

 quently the soil derived by disintegration from them, have a widely 

 different physical character. Future ecological studies in the vicinity 

 of Copley may well correlate the distribution of the vegetation with 

 the nature of the soil and with the rocks from which it has been derived, 

 as has been done by Osborne in the Mount Lofty Ranges near Adelaide 

 (1914:114). 



Such observations as were made by me on soils will be given, to- 

 gether with the running account of the most striking features of each 

 of the habitats studied. It will suffice to say, as would be supposed 

 from what is known of the local geology as above suggested, that the 

 soils are very various. For example, on the plain about the village 



