l."56 llip (t<'oI(i(ju i)f (ho (lold Fif'Jdx of llrtiixli Gainna, 



character of tlie gneiss is inediuin to line in grain with numerous veins 

 of ])egniatite intersecting it in all directions. The j^egmatite, as seen 

 at Marshall llapids, at Kesterbrake Ra2)ids, and at Wariniambo 

 Cataracts, is fre([uently of a very coarse texture, showing white and 

 pinkish coloured feldspar-crystals from three to four inches in length. 

 Above Iren Rapids the gneiss is of a coarser texture than it is at tlie 

 lower rapids of this series. At Stile Ilapids the gneiss is intersected 

 by a coarse-textured, grey granitite containing blebs of })luish 

 opalescent quartz. At Tarpe Rapids, near the left bank of the rivei-, 

 the gneiss is traversed by a dyke of fine-gl•ail^ed diabase, about seven 

 feet in width, which strikes approximately south-east and north-west 

 aci'oss the left channel of the river. 



From Maripa Cataracts, at the head of the series of cataracts over 

 gneiss, the river for about three and a half miles flows through a belt of 

 gneissose granite. In this the channels of the river follow very tortuous 

 courses between numerous small islets and innumerable rocks. At 

 Maripa Cataracts the granite is a coarse-textured, pinkish to grey 

 granitite which is traversed by a few veins of pegmatite, usually from 

 one to two inches in width. Above the Maripa series of rapids and 

 cataracts are the Pojjikai Rapids, where the rocks exposed consist of 

 an epidote-hornblende-granitite, with a marked gneissose structure 

 approximating to that of a granitoidal gneiss, which later gives place 

 to a pink-coloured, medium-textured granitite. Some immense rocks 

 and masses of the coarse granite near the lower parts of these rapiils 

 are known as the Poj^ikai Rocks. The next series, the Yamatuk Rapids, 

 are over coarse-grained, grey granitite, wdiicli is traversed by a very 

 fine-grained, pinkish granitite lying in intrusive sheets. Near the 

 Yamatuk Rapids attention is drawn to a weathered mass of granite 

 roughly resembling a horse's head, called the Yamatuk Rock. 



Somewhat higher up the channel than the Yamatuk Rock on the 

 left bank is the lower end of Wassai or Tramway Hole, a narrow 

 channel through which the water rushes with great force and at a high 

 velocity. The lower parts of this channel are cut through granitite, 

 the upper part through coarse-textured hornblende-granitite-gneiss 

 intersected here and there by veins of fine-grained granitite. In the 

 main channel, above the lower end of Tramway Hole, the Tokainia 

 Rapids occur over granitite, while above its upper part, at Kumana 

 Rapids, and at near its head, great rounded masses of fine-grained, 

 grey granitite-gneiss are seen. For about three miles and a half above 

 Wassai Hole the channel is cut through granitite-gneiss. 



Near Kapasi Mission Station (now abandoned) and at Kapasi 

 Rapids, south of the station, great rounded masses of coarse-grained 

 hornblende-Hranitite are exposed ; the same rock occurs at and 

 near Pikaima Island, and also at several small rapids, while here 

 and there along Tupeku Channel a finer-textured variety is seen. 

 About a mile and a half up this channel a dyke of dark-grey, fine- 

 grained quartz-diorite, varying in breadth from five to ten feet, was 

 noticed intersecting the hornblende-graiutite. The belt of horn- 

 l)lende iiranitite is about four miles in width. From a little south of 



