530 ./. T. Jutson: 



but they are presumably scarce. Outside the Warrandyte dis- 

 trict a trilobite, probably an lUaenus, and some brachiopods 

 and corals have been found. The fossils have not yet been 

 examined, so little can be said with re^-ard to them. 



The sediments indicate that at Warrandyte there was an old 

 Silurian shore line, close to which the conglomerates, grits and 

 sandstones were laid down. These are also interbedded with 

 shaly rocks, the alternations often beinji very rapid, thus show- 

 ing shalloAv-water conditions. To the south of Warrandyte 

 these coarse rocks seem to gradually pass into those of finer 

 grain. A strong pitch conceals their northward extension, while 

 they do not occur to the east or west, by reason of passing be- 

 neath the great mass of rocks that form the Warrandyte Anti- 

 cline. Possibly their extent horizontally was never very great. 

 The direction of the old shore line cannot be indicated, and all 

 that can be said at present is that it was probably not to the south. 



On the top of the shallow-water beds is a great thickness oi 

 phales, occasionally separated by thin bands of sandstones. 

 These by their general absence of coarser material (in one or 

 two places a thin band of grit or conglomerate has been found) 

 appear to have been laid down in moderately deep water. On 

 the top of these in the Croydon district is the narrow band of 

 silicified sandstones. In the western part of the area the thick 

 shales are succeeded by rocks of the type seen near Mel- 

 bourne, alternating sandstones and shales. From the great 

 thickness of the shaly rocks, it is evident that there was a 

 gradually-sinking shore line, with which however the sedimen- 

 tation kept place, and so prevented very deep-water conditions 

 from resulting. 



(e) Age and Thickness of the Eorks. 



Pending the examin;ition of the fossils, nothing definite can 

 be said as to the age of the rocks throughout the area. Prof. 

 Gregory has indicated (9, Plate xxv. Fig. 5) that the rocks 

 of the Warrandyte Anticline are of Melbournian age, and has 

 also suggested (lb. p. 172) that the Yeringian series might be 

 expected to appear in the syncline to the west of the Warran- 

 dyte Anticline) i.e.. the Bulleen Syncline). 



