BY L,. KEITH WARiD, B.A., B.B. 



12.9 



a portion of the West Coast Range conglomerate series 

 and the overlying sandstone. They have not been ob- 

 served in any other sandstones, and never in actual 

 association with any other fossils. So we may apparently 

 conclude with safety that the tubicolar sandstone is the 

 next succeeding formation to the West Coast Range 

 cong'lomerate (where the full sequence is represented) 

 and of slightly less antiquity. 



Moreover, during the recent exploration of the 

 country in the vicinity of the Frenchman's Cap, the 

 writer found an extensive development of the tubicolar 

 sandstone in the Loddon River Valley. Here it is con- 

 formably overlain by another white sandstone of similar 

 grain ; and in this latter sandstone are certain peculiar 

 discoidal impressions. The exact nature of these mark- 

 ings is unknown, and Mr. Etheridge, of the Australian 

 Museum, to whom specimens have been referred, has 

 declined to express an opinion concerning them, since 

 no traces of the organic structure remain. 



Mr. W. H. Twelvetrees has pointed out that entirely 

 similar, but smaller, discoidal moulds exist in the fossil- 

 iferous Upper Cambrian beds of Caroline Creek. In 

 the event that the discoidal markings should prove to 

 possess stratigraphical value, the discoidal sandstone 

 must belong to the Cambrian system. 



It should perhaps be here stated that the tubicolar 

 sandstone has formerly been looked upon as of Silurian 

 age, the reason 'being- that at Zeehan and the Five-mile 

 Rise strata bearing Silurian fossils have been found 

 above this sandstone. 



A re-examination of the occurrences of the tubicolar 

 sandstone is therefore required, v/ith a view to the dis- 

 covery of a possible break in the succession. Should 

 such a break be found between the pipestem rock and 

 the superincumbent Silurian, the explanation of the 

 previous classification of the strata will be provided. 



4. The Denison Range is built up of a great series 

 of siliceous sediments — crystalline pebbly sandstones, 

 quartzites, and conglomerates. These rocks have been 

 traced without interruption for many miles from the 

 Thumbs across the gorge of the Gordon River, and 

 northwards along the Denison Range. 



