84 Transactions. 



on west side of Taupo ; Whangamata Bay, West Taupo ; Titi- 

 raupenga. Khyolites were found in several places. Some 

 contained quartz, brown hornblende, and augite. Spberulitic 

 and axiolitic types were mentioned, and a banded type from 

 Motutaiko Island, in Lake Taupo. 



In a second paper* the rocks of Tongariro are described 

 as typical augite-andesites, but in a few instances there was a 

 little olivine — e.g., the summit of Tongariro, at the red crater, 

 and at Otukou. It is noticeable that in all of Professor 

 Thomas's descriptions there is no mention of the occurrence 

 of rhombic pyroxene. 



Captain Huttonf described many rocks from this district. 

 Rhyolites are recorded from Taupo ; hornblende-rhyolite, from 

 Lake Tarawera and Lake Rotorua ; augite-rhyolite, from Atea- 

 muri ; enstatite - rhyolite, from Lake Taupo ; chlorite-rhyo- 

 lite, from Okaro ; pitchstone, from Maketu, Tauranga, and 

 Mayor Island ; spherulitic pitchstone, from Eotorua ; obsi- 

 dian, from Mayor Island, Taupo, and Lake Rotoiti. Trachyte 

 is recorded from the Sugarloaves, Taranaki, but subsequently 

 Hutton classified this rock as an andesitej ; from Whangarei, 

 based on an identification of Cox§ ; from Runanga, Napier- 

 Taupo Road, based on an identification of Hector ||. Horn- 

 blende - andesites are recorded from Sugarloaves, Taranaki ; 

 Mount Egmont ; eastern base of Mount Ruapehu ; Tokatoka ; 

 Kaipara. Augite - andesites, from Mount Egmont ; Mount 

 Pirongia ; Okaro ; Mount Tarawera, eruption of 1886. Ensta- 

 tite-andesite, from Sugarloaves, Taranaki ; Ruapehu ; Horohoro ; 

 White Island ; Puponga, in Manukau Harbour ; Helensville ; 

 Kamiti, in Kaipara Harbour ; Whangarei Heads. Olivine-ande- 

 site, from Mount Egmont. A dolerite is recorded from Kake- 

 puku ; and basalt from Mount Eden and Rangitoto, near 

 Auckland. ■ t 



Thomas, ^[ in a report on the Tarawera eruption, published 

 by the New Zealand Government in 1888, has mentioned the 

 rocks of Mount Edgecumbe as augite-andesite, and the lava 

 emitted as bombs from Tarawera in 1886 is also described under 

 the same name. 



Hill** has described the rocks of Ruapehu as basalt, trachyte, 

 and andesite. 



* Thomas, Trans. N.Z. Inst., vol. xxi. p. 349 et acq. 

 t Hutton, Royal Soc. N.S.W., 1889, p. L02 U scq. 

 t Hutton, Trans. N.Z. Inst,, vol. xxxi, p. 483. 

 § Cox, Geological Reports, 1876-77, p. 95. 

 || Heotor, Geological Reports, 1870-71. 



^1 Thomas, " Report on Eruption of Tarawera,'' pp. 13 and 58. 

 ** Hill, Trans. N.Z. Inst., vol. xxiv, p. 617; also Trans. Aust, Assoc 

 Adv. Sci., vol. iii, p. 170. 



