412 W. J. McGee — Geology of the Mississippi Valley. 



course is diverted, and it follows the strike of the rocks for some 

 distance. 



Along the top of the range west of the " flat," and crossing the 

 Wellington Road, another greenstone dyke or outcrop occurs, about 

 ten chains wide, and also following the strike in general direction. 

 These dykes, which are all, more or less, of the same character 

 as that already described, run towards the head of " the flat " and 

 beyond it, — the ranges being confusedly intersected with " blows " 

 and outcrops of greenstone, containing quartz-reefs. These reefs 

 may, at some time, prove to be auriferous, like those at Merinda 

 and Gulgong. 



A vei-y peculiar isolated conglomerate-capped hill occurs to the 

 north-west of the "Two-mile-flat." The conglomerate, which is 

 about 70 feet thick, and 100 feet above the river, consists of loosely 

 cemented green, yellow, and purple grits with veins of calcite, 

 purple shales, mottled and banded grits, decomposed greenstone, 

 and small and large grained metamorphic breccias from the imme- 

 diate neighbourhood, — the whole imbedded in a hard, brittle, ferru- 

 ginous clay, and the large flat boulders and pebbles being all coated 

 with a glistening purple polish. This conglomerate rests uncon- 

 formably (horizontally) on the tilted Silurian rocks, and is probably 

 of Carboniferous age, — or younger. It bears a considerable resem- 

 blance to the rock from Mount Timbertop, in Gippsland (Case x. 

 No. 41, Victorian National Museum Catalogue), and others from the 

 Stony or Moitun Creek, Dargo Road, Gippsland (Case x. No. 17). 



The lead, after leaving the Two-mile-flat, crosses the river to its 

 north side, and is there only represented by a thin deposit of newer 

 drift, the basalt and older drift having been entirely denuded away. 

 The gold obtained was not in payable quantity, and the lead was not 

 properly traced. 



To the eastward is a schist range, on both sides of which the 

 greenstone dyke, before mentioned, crops out. This dyke appa- 

 rently splits, or rather underlies and crops out on both sides of, a 

 schist hill near Miller's Claim, — the range, with its accompanying 

 parallel outcrops of greenstone, runs in the strike of the rocks 

 (N. 25° W.) up the east side of the valley of the Sandy or Cudge- 

 beyong Creek. 



(To be concluded in our next Number.) 



IV. — Notes on the Surface Geology of a Part of the 



Mississippi Valley. 1 



By "W. J. McGee, Esq., etc., etc., 



of Farley, Iowa. 



Kames, sar, and minor topographical features. — Karnes and asar 



are usually found associated. Indeed, the one class of elevations 



shades into the other so gradually that it is sometimes impossible to 



draw the line between them. Though the kames may occur singly, 



they are often in ranges of several, perhaps extending for miles. 



Each is usually elliptical in outline, and its longer axis corresponds 



1 Concluded from page 361. 



