nortX KXPEDITIOX — flKXERAL OEOLOOY. 31 



upon tlioso are quartzitos (sonietimos coiiglompratie), (loloiiiitic limost-onf", and 

 occcasionally clay-slates, and are classed as " Cainl)iiaii ('?)." In the main valleys 

 of the ranges are ilat-topped hills of quartzite, conglomerate, iroiist(jne, and fei'ru- 

 ginous sandstone ; these beds belong to the Sec(^ndary or Tertiary age. 



Xr. — CiiKwiXfiS, Charles, "Geological Notes on the Upper Finke Basin," 

 Trans. Roy. Soc. S.A., vol. xiv., pp. 247-255, pi. x., 1891. The stratigraphical 

 .sequence ,as estal)lished by the author is as follows : — 



Pre-Silurian. — Developed in the McDonnell Ranges. [Certain limestones 

 and shales are included, which tlie writers refer to the next scries.] 



Silurian. —Comprising the "McDonnell Ranges south." This assigned po.si- 

 tion is leased on the fossil evidence as interpreted )jy Prof. Tate (p. 255). [Herein 

 are included the Post-Ordovician congloinei'ates of tlie present writers.] 



Drvoniax. — Rocks of this age occupy, according to the autlior, tlu; synclinal 

 folds of the Silurian quartzites ; to wliich also belongs the ( )oiaminna sandstone. 

 [These we fail to separate stratigi'aplncally and sti'ucturally from the Ordoviciaii.] 



jNIesozoic (?) — To this period belong a coarse sandstone formation, forming 

 flat-topped hills in the lie/irt of the McDonnell Range. [Tiu^ development at Glen 

 Helen Station referred to l)y the author consists of the residue of the waste of the 

 gneissic and granitic rocks, and offers no analogy to the Cretaceous rocks on tiie 

 southern Ijorders of the Primary as suggested by Brown (x., p. 2).] 



Cretaceous. — A limestone rubljle with flints an<l gypsum resting uncon- 

 fonnably on the supposed eai'lier Mesozoic rocks, at the junction of the Palmer 

 and Walker Creeks, is in the opinion of the writers a recent travertine. 



Tertiary. — " Tite cone-shaped hills composed of clay-grit-, horizontally bedded," 

 as seen l)y us at tlie extreme of Pct(>rmann Creek, on the Walker, and Vale oi 

 Tempe, are outliers of low-dipping Ordovician sandstones. 



XII.— Brown, Henry Y. L., " Report on Leigh Creek Coalfield," Pari. Paper, 

 No. 158, 1891, p. 12, states that "lying unconformably on the crystalline meta- 

 morphic, gneissis, and granitic archaean rocks of the McDonnell Ranges there ai-e 

 two other rock-systems unconformable to eacli other. The lower of these consists 

 of ((uartzite, ([uartzite conglomerate, dolomitic limestones, etc., striking E. and W. 

 in descending the Finke they appear at intervals as highly-inclined beds, 

 tlie outcropi)iiig edges of synclinal troughs in wjiicii rest th(^ upper .system. [These 

 are referred to Cambrian.] The up[)er system consists of sandstone quartzite, 



