BY W. G. WOOLNOUGH. 465 



indicating the lapse of an enormous period of time between the 

 injection of the granite and the formation of the tuflf. 



The cave limestone of Tawaleka is considerably folded, the 

 contortion being connected with that of the tuffs further down 

 the river. The latter were not visited during my second 

 expedition. 



A splendid view of a mountain called Nasikawa, east of 

 Natuatuacoko, is obtained from the hills north of Tawaleka. 

 From this distance it appears to have the structure of a mountain 

 composed of dipping beds of varying hardness, dip slopes and 

 scarps being recognisable. The dip is about W.N.W. at 40°. 



Most of the higher points in the district are composed of level- 

 bedded soapstone. This is met with unconformably overlying 

 the slaty rock at Namoli, and there attains an altitude of iully 

 1,500 feet above the river-bed, and about 2,100 feet above sea- 

 level. A similar material occurs unconformably (?) overlying the 

 cave limestone at Tawaleka. 



The top 1,000 feet, or thereabouts, of Muanivatu, consist of a 

 mass of columnar pyroxene andesite. It is possible that this 

 may be a sill, but it is more probably a flow. It yields magnifi- 

 cent precipices. 



Summary of Section ix. — This district, lying not 

 far from the head of the navigable water of the Sigatoka, was so 

 far removed from my base that I have not yet explored it 

 thoroughly. While in the district, meteorological conditions 

 were extremely unfavourable. I have seen enough, however, to 

 prove that the energies of any future expedition should be con- 

 centrated on the solution of the many problems presented by it. 



Granitic rocks do not occur in the bed of the main stream, but 

 highly jointed, ancient-looking tuffs and slaty rocks form the bed, 

 from about Waisa at least to Koroilevu. Granites and related rocks 

 are extensively exposed in the group of tributary streams which 

 meet the main river between Namoli and Waibasaga, These are 

 about the same general altitude as the granitic rocks of Naroko- 

 rokoyawa, and undoubtedly form part of the ancient peneplain 

 referred to under Section vii. of this paper. A granite-bearing 



