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Transactions. 



- .-- - V I - - •.-; g > ^. 



II. Section at Cliff on River-bank, South Head, Kakanui. 



a. Limestone, b. Marl. c. Coralline limestone, d. Tuffs and breccia, 

 e. Hard cap of breccia. /. Limestone, g. Clay. h. Gravel. 



A limestone of unknown thickness forms the base ; this is 

 covered conformably by a marl or calcareous mud, 26 ft. thick, 

 the upper 6 in. being coralline limestone ; then follows 60 ft. of 

 rather fine volcanic tuff containing small cleavage fragments of 

 hornblende, the top layer of 1 ft. being set in crystalline calcite, 

 rather hard, and containing most of the minerals found else- 

 where in the breccia. This is covered conformably by at least 

 40 ft. of limestone, containing many fossils. Clay then forms 

 the cliffs to the mouth of the river. An isolated exposure 

 of limestone occurs just at the river-mouth, its relations 

 being obscured by gravel and an artificial breakwater erected 

 there. 



A few yards further on, towards the east, the " mineral 

 breccia " occurs again, and forms the cliffs right round the South 

 Head for about three-quarters of a mile. It contains fossils 

 in its upper layers, and going southwards disappears con- 

 formably under a limestone 12 ft. thick. This limestone is 

 covered conformably by a glauconitic greensand, and then 

 gravel forms the cliffs for a mile to the south. 



III. On Kakantji South Head. (Distance, J mile.) 

 a. Mineral breccia, b. Limestone, c. Greensand. d. Gravel, e. Clay. 



A bluish clay forms the beach for this mile to the south, 

 but does not form cliffs, being only a few feet above sea-level. 

 Its actual contact with the greensand cannot be seen. 



The dips of the breccia and the associated rocks vary very 

 rapidly from place to place. At the south end of the North 



