Cox. — On the Mineralogy of New Zealand. 401 



Halloysite, 'j^\ Si + 4 H. — The occurrence of this mineral in decom- 

 posing basalts around Dunedin is mentioned by Dr. Hector (Jurors' Eep. 

 N.Z. Ex., 1865, p. 438), and a specimen from the Water of Leith is de- 

 scribed by Professor Liversidge (Trans. N.Z. Inst., vol. x., p. 499) as 

 follows : — " An opaque white earthy substance, soft and soapy ; associated 

 with it is a little black halloysite ; when immersed in water it gives off air- 

 bubbles rapidly, accompanied by a singing sound ; falls to pieces and 

 becomes translucent on the thin edges ; breaks with a conchoidal fracture ; 

 adheres strongly to the tongue ; yields to the thumb-nail, and affords a 

 shining streak; possesses an earthy smell." A sample of an impure form 

 from Scinde Island, Napier, where it occurs in considerable quantities (Col. 

 Mus. and Lab. Eep., vii., p. 18), was forwarded to the Museum in 1872, 

 and had the following composition : — 



OlllL it . . 



Sesquioxide of iron 



. . . . . oa £l£i 



5-82 



Alumina 



24-34 



Lime 



2-02 



Magnesia 



253 



Water 



4-81 



Alkalies and loss 



2-26 



100-00 



the high proportion of silica being due to the presence of grains of free 

 quartz, which constitute the principal impurity. A specimen from the Bay 

 of Islands was forwarded by Mr. J. Williamson in 1874, and is of a 

 yellowish-brown colour, and very fine grain ; three specimens from the 

 Drury and Hunua Eanges were forwarded by the Hon. H. Chamberlin in 

 1875, and a specimen collected from Whangaroa Harbour, by Mr. A. 

 McKay, during the same year. 



Fuller's Earth. — Specimens from Great Barrier Island and the Hot 

 Springs, were exhibited at the Dunedin Exhibition of 1865, by the 

 Auckland local committee, and are mentioned (Jurors' Eep. N.Z. Ex., 

 1865, p. 253). 



Palagonite, (A^-Fe) Si 3 + 3 (Ca, Mg, Na) Si -f 10 H.— The occurrence 

 of this mineral as angular fragments in palagonite tufas is mentioned by Dr. 

 v. Haast (Jurors' Eep. N.Z. Ex., 1865, p. 257), at Harper Hills, near the 

 Selwyn, and at Two Brothers, Ashburton, as also another variety changing 

 insensibly into a pitch opal, enclosing leaves and stalks silicifiecl, in the same 

 localities. A specimen from Taipo Hill, Otago, was forwarded in 1868 by 

 Mr. C. Teschmaker, where it occurs as a large seam 60 feet thick, running 

 in the direction of a limestone quarry. Its characters, as described by Mr. 

 Skey, are — massive ; colour, black ; hardness, 4-5 ; somewhat friable ; is 

 26 



