Canterbury and Westland. 349 



of a bed of chocolate-coloured tufa, resembling some of the so-called 

 aqueous lava-streams (lava d'aqua of Italy), reposing directly upon the 

 remnant of the older crater wall, shows that similar causes, as obtained 

 in the ancient Kingdom of Naples, were also here in operation. 



I examined repeatedly the conglomeratic and agglomeratic beds in 

 question for fossils, but in vain, not the least sign of marine shells or 

 other organic life being in existence. The vent of the last eruption 

 lies just below the remnant of the ancient crater wall, exposed in the 

 north-eastern face of Quail Island. The loose agglomerate beds, of 

 which it consists, are mostly of a red colour, and, like the domite dykes 

 by which they are crossed are much altered. The chocolate- coloured tufa 

 bed on the western corner of the cliff is covered by a large conglo- 

 meratic deposit, similar in its nature to those which are interstratified 

 on the eastern side with the basaltic lava-streams. It rises to the 

 summit of the island, and is overlaid by a number of streams of basalt 

 which form the whole western side of the island, with the exception of a 

 very few spots where remnants of the older crater are exposed to our 

 view. After the formation of Quail Island, and the few other small 

 centres of basaltic discharges already pointed out, no other volcanic 

 eruptions seem to have taken place, Banks' Peninsula rising afterwards 

 a few hundred feet and maintaining with the exception of small oscil- 

 lations, its present level ; at the same time it remained surrounded by 

 the sea for a considerable period. There is clear evidence, as I shall 

 point out in the sequel, that even during its occupation by an 

 autochthonic population, the straits round the island had not yet been 

 closed by the drif tsands and shingle advancing from the south. During 

 this period, without doubt of long duration, the deposits of loess were 

 formed on its slopes of which I shall treat in one of the next chapters. 



