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574 either way; nor are we justified in ascribing to Tongariro and its adjacent volcanoes the origin of the whole of this pumice, until a thorough exploration of the mountainous Urewera country shall have proved that it did not emanate from some nearer source. That volcanic rocks exist somewhere in that direction is proved by the finding of volcanic pebbles in the bed of the Wairoa River, which must have come down the Hangarou, one of its main branches, and which has its source somewhere in the neighbourhood of Maungapohatu, a lofty mountain some 20 miles to the north and east of Waikaremoana.

Of other recent formations present there are the river terraces, sand dunes, lagoons along the coast, caves in the limestone, and the fine gravel along the beach. The course of the Mohaka River presents some fine examples of the first. Near its mouth I have counted as many as eleven separate and distinct terraces, some high, some of only a few feet. These are all cut out of the solid Papa rock, and in the case of the higher one of all (which forms the true valley of the river) this has been spread over with a deposit of shingle derived from the slate mountains of the interior, of from six to eight feet thick. It forms a plain about ten miles long by a varying width of from one to two miles. It is covered thickly with before mentioned. Its general level is from 200 to 300 feet above the present river, which has cut for itself a deep precipitous channel, the sides of which afford an excellent section of the various beds through which it passes. The terraces of the Wairoa Eiver are not so well developed. There is one large one, however, which extends up both the main branches at a general height of from 50 to 150 feet above the river level. This is also generally covered with pumice, but not to so great an extent as those of Mohaka, whilst the recent and lower ones are nearly free from it. Of sand dunes there are not many, the coast being generally bold and precipitous. They are found at the low narrow neck of land connecting the Mahia Peninsula with the main (and which narrow neck, I may here observe, would, by a depression of 20 feet, again be submerged, thus making the Mahia an island), and also about the Whakeki Lagoon, which owes its origin to the banking up of the sand and gravel from the beach. A regular gradation may be observed in the sizes of the gravel on the beaches, which at Petane is small shingle, but sets smaller and smaller until at Nuhaka it has become ground down into coarse sand.

The caves of the limestone formation are numerous, but I never had time to visit them.

The Natives relate stories of most wonderful caves, grottos, and fissures as existing in the Whakapunake Mountain. They also stated that in one of these caves, the last of the Moas had his residence, and that their