344 Transactions. — Geology. 



and the eye stretches over vast fields of rugged hummocky 

 lava. 



The second, or Eed Crater, lies further to the north, and is 

 interesting as showing the signs of recent activity. The 

 crater has very steep sides, so that from the west at least it is 

 not possible to descend into it. The upper part of the crater 

 is formed by a great thickness of beds of dark blood-red 

 scoriae having an extremely close resemblance to the layers of 

 scoriae of the Tarawera eruption which lie piled up on the 

 borders of the fissure on the Tarawera Mountain. It is said 

 that steam can be frequently seen issuing from this crater ; 

 but none was visible on the occasion of my visit. Around the 

 margin of this crater blocks of a dark heavy lava, having the 

 appearance of a basalt, and more basic than the usual lavas of 

 the mountain, are to be found. Across the floor of the crater 

 is a small lava-stream. 



To the north of the Eed Crater, on the part of the moun- 

 tain called Te Mari, is an old crater of considerable size. 

 Lying to the east of this, and separated by a comparatively 

 low ridge of rock, is another crater, containing a lake of the 

 most beautiful blue water (see Plate XXXI.) ; whilst on a ridge 

 between this and the Eed Crater are two much smaller lake- 

 lets, one of which from its colour has been called Eotopou- 

 namu (Greenstone Lake). 



On the north-eastern slope of Te Mari is yet another crater 

 of considerable size, and close to this, as already mentioned, 

 there is a large but intermittent escape of steam. 



Lake Taupo. — It is not my intention to enter here into a 

 detailed description of Lake Taupo and the surrounding 

 country, but merely to mention such points as we shall have 

 occasion to refer to hereafter or as have not been previously 

 described. The lake has an area of nearly 242 square miles; it 

 is 24^ miles in length and l&h miles in extreme width, and has 

 a shape which has a general resemblance to that of the conti- 

 nent of xlfrica. In many places the lake is bounded by steep 

 cliffs of lava and associated tuffs. That the lake formerly 

 stood at a higher level is clearly shown by the terraces around 

 it, which are continued up some of the small valleys leading 

 into the lake. One terrace stands at a height of 100ft. above 

 the present water-level of the lake. The accompanying plate 

 (Plate XXXII.) shows this terrace at the south end of the lake, 

 about three miles from Tokaanu, looking in a northerly direc- 

 tion. Another well-marked terrace lies at the height of 300ft. 

 to 400ft. above the lake. 



The lavas at the north, east, and part of the western sides 

 are rhyolites ; at the south end they are chiefly augite-ande- 

 sites. The pumice-deposits which form so remarkable a 

 feature of the Taupo district are found to a greater or less 



