president's address — SECTION c. 149 



Gastrioceras Jacksoni, sp. no v. (the largest gonatite yet found in Aus- 

 tralia, and of an entirely different type to the incomplete forms so far 

 described). 



The facies of these fossils is more akin to the Carboniferous than 

 the higher Permo-Carboniferous, and only four species are with certainty 

 identical with those found in the Permo-Carboniferous rocks of Eastern 

 Australia, viz. : — Nuhecularia, Productus subquadratus, Fenestella 

 fossula, and Aviculopecten Sprenti. 



Associated with the Marine Series is a boulder bed, the debris of 

 which strew the surface for a considerable distance; but there has 

 as yet been no opportunity of investigating these beds in any detail. 

 So far I have seen no striated pebbles among the boulders. 



About 25 miles lower down the river, in the vicinity of Mingenew, 

 and close to the railway line, are a series of ferruginous sandstones, 

 on a higher horizon than the limestones, which remind one very forcibly 

 of the Sandstone Series as developed in the Kennedy Range of the 

 Gascoyne River. These beds have yielded the following fossils : — 

 Dielasma nobilis, sp. nov. ; Dielasma hastata, Dana ; Spirifera, 

 sp. ind. ; Spirifera avicula, E. B. Sby. ; Cyrtina carbonaria, var. Aus- 

 tralasica, Eth. fil. ; Cleiothyris Macleayana, Eth. fil. ; Productus sub- 

 quadratus, Morris ; Productus brachythoeris, E. B. Sby. ; Chonetes, 

 sp. ind. ; Deltopecten subquinquelineatus, McCoy ; Modiola (?) sp. ind. ; 

 Myalina (?) Mingenewensis, sp. nov. ; Fenestella or Protoretepora. 



On the whole it seems that the aspect of the fossils is that of the 

 Permo-Carboniferous of New South Wales. It thus seems that there 

 are m the Irwin River valley beds of a Carboniferous and Permo- 

 Carboniferous Age, and that the coal seams may be possibly the equiva- 

 lents of the Greta Coal Measures of New South Wales. 



The Collie River beds, which attain a thickness of a little over 

 2,000ft., are of considerable economic importance by reason of the 

 fact that they contain coal seams to a total thickness of about 137ft., 

 and are of some scientific interest in their relation to the important 

 question of the distribution of the Glossopteris flora. 



The Collie River Coalfield lies to the east of Bunbury, and south of 

 Perth, near the north-western edge of the tableland which succeeds the 

 coastal plain. The field itself is traversed by the Collie River at an 

 altitude of about 600ft. above the level of the sea. The area occupied 

 by the Collie River Coal Measures is approximately 500 square miles. 

 The beds consist of alternations of shales, sandstones, and grits, which 

 rest directly upon granite schists and other crvstalline rocks. The 

 boundary of the field is, with one local exception, everywhere defined 

 by faults : on the south-western side of the field the boundary fault has 

 been estimated to have a down-throw to the north-east of at least 2,000ft. 



There are several coal seams in the field, of variable thickness, 

 they consist in descending order of — Cardiff No. 1 seam, 9ft. to 12ft. 

 thick ; Cardiff No. 2 (or Boulder seam), 7ft. ; Collie Burn No. 1 seam, 

 9ft. thick ; Collie Burn No. 2 seam, 6ft. to 7ft. lOin. ; coal (no name), 

 8ft. ; Proprietary No. 1 seam, 4ft. to 8ft. ; Proprietary No. 2 seam, 

 5ft. to 7ft. 6in. ; Wallsend seam, 9ft. to 17ft. thick. 



