148 president's address — section c. 



bore, however, which, did not pierce the whole thickness of the Car- 

 boniferous rocks, gave no sign of the boulder bed. From the few 

 salient features pointed out it appears quite clear that the glacial 

 conglomerate is associated and interbedded with the fossiliferous 

 limestones low down in the Carboniferous series, as developed in this 

 part of Australasia. 



In the year 1897 I made a traverse up the Murchison Valley in an 

 exceptionally dry season, which seriously interfered with geological 

 investigation, and at a point in the bed of the river about 100 miles 

 south of the boulder bed last mentioned a conglomerate and breccia 

 composed of angular fragments of a quasi-vitreous quartzite dipping 

 at a low angle to the east was met with ; the base of the conglomerate 

 was not visible anywhere. The most important and significant feature 

 in this section is the fact that many of the pebbles were covered with 

 scratches, not unlike slickensides. A few yards lower down the river 

 are a few beds of cross-bedded sandstones and fine conglomerates 

 dipping east at an angle of about 20°. One of the beds has been scored 

 to such a degree as to produce surfaces as smooth and polished as plate- 

 glass. The question arises, is this a portion of a glaciated pavement, 

 or is it due to faulting ? If the latter, the faulting is nearly horizontal. 

 Some distance further up the river, near the 40-mile crossing and 

 water reserve 1005, the sedimentary beds are interstratified with coarse 

 conglomerates or boulder beds : the boulders are principally quartz, 

 though pebbles of sandstone and granite occur. I detected no scratched 

 boulders in this section, though circumstances did not admit of any 

 detailed search being made. The important point in connection with 

 these conglomerates containing the scratched boulders is that they 

 form part of what is at present believed to be the southern extension 

 of the Carboniferous series of the Gascoyne, and form a connecting 

 link between the latter and the Irwin River series, to which reference 

 will be made later. 



Beneath the Jurassic rocks of the Champion Bay district, and in 

 the valley of the Irwin River and its tributaries, is a fairly extensive 

 development of Carboniferous and Permo-Carboniferous beds. In 

 this district, as in Kimberley, it seems possible to divide the strata into 

 two distinct series, viz., the lower, the limestone, and the upper, pr sand- 

 stone, series. 



Beneath the Irwin River coal seams are a calcareous shale and 

 limestones, yielding a series of fossils, which have been carefully ex- 

 amined and described by Mr. Etheridge of the AustraUan Museum, and 

 will shortly appear as one of the bulletins of the geological survey of 

 Western Australia. The following fossils occur in these beds : — 

 Nuhecularia Stephensi, Howchin ; Pleurophjjllum Australe, Hinde ; 

 Fenestella fossula, Lonsd ; Dielasma, sp. ; Seminula suhtilita, Hall ; 

 Spirt f era, sp. ; Reticularia lineata, Martin ; Productus semireticulatus, 

 Martin ; Productus tenuistriatus, var. Foord, Eth. fil. ; Productus 

 iindatus, Defrance ; Productus subquadratus, Morris (?) ; Chonetes 

 Pratti, Dav. ; Aviculopecten Sprenti, Johnston ; Conocardium, sp. 

 Brown ; Stutchhuria, sp. Eth. fil. ; Bellerophon costatus, J. de C. Sby., 



