Mulgan. — The Waitemata Series. 



431 



After passing this spot, about a mile beyond a headland 

 called " The Horn," the outcrops of grit disappear, and are 

 not met with until about five miles further on, when they 

 again become plentiful. They are similar in every respect to 

 those already described. One exposure, however, deserves 

 special mention. It 



i Shag 



Fig. 



9. 



Cong/ornerafe 



Sha/e 



F/ne grit 

 Sha/e 



F/ne grit — 12 ft : 



Shore fine 



3ft. 



4ft. 

 2ft. 



2ft. 



Sketch at Shag Point, showing distinct 

 bands of conglomerate and grit. 



Point. 

 As shown in sketch 

 (fig. 9), this consists 

 of a band of con- 

 glomerate composed of 

 fragments of a close- 

 grained andesite, 6 in. 

 to 8 in. in diameter, 

 much waterworn and 

 rounded. This bed, 3 ft. 

 in thickness, rests on 

 beds of shale some 4ft. 

 thick ; and this, again, 

 is underlaid by a layer 

 of grit 2 ft. in thick- 

 ness. A small layer 

 of shale separates this 

 from another band of 

 grit 12 ft. thick, which 

 extends to and passes 

 under the shore-line. 

 The strata here dip 



into the hill and disappear. To the west the coast-line 

 curves round to form a bay, whilst to the east the cliffs give 

 place to a low gently sloping bank covered with vegetation ; 

 hence this is the only section available. x\bove, the vegeta- 

 tion extends down to the conglomerate and the rocks are com- 

 pletely decomposed, so that it is impossible to say what may 

 overlie the band — most probably the ordinary Waitemata 

 sandstones and shales. It would appear from the section that 

 there are at least two, and possibly three, distinct bands, one 

 of conglomerate and two of grit, separated by layers of shale. 

 This conjecture is rendered all the more probable from the 

 fact that the conglomerate overlies the grit. Here, however, 

 we are approaching a country where in early Tertiary times 

 there was great volcanic activity ; hence it is not surprising 

 to find an increase in the amount of volcanic material inter- 

 stratified with the ordinary sedimentary deposits. 



The country from Puponga Point northwards consists of 

 coarse volcanic conglomerate intersected by dykes and lava- 

 streams of andesite and beds of volcanic tuff. Masses of 

 Waitemata beds occur in places mingled with the conglomer- 



