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Ex., 1865, p. 256), and as porcelain jasper from Petrifying Gully, Mount Somers (Geol. Rep., 1873–74, pp. 9, 10); by Dr. v. Hochstetter in the tuffs and conglomerates of Coromandel (New Zealand, 1863, Eng. ed., p. 96); by Mr. J. C. Crawford, at Ruamahunga (Trans. N.Z. Inst., vol. ii., p. 345), and by Prof. Liversidge at Clutha, and as green jasper at Moeraki (Trans. N.Z. Inst., vol. x., p. 496). He describes the specimen from Moeraki as follows:—"Variegated with reddish brown streaks; a little chalcedony on one surface. The green colour is mainly due to the presence of protoxide of iron; there is also manganese present in small quantity. On heating in a closed tube it decrepitates slightly, blackens and gives off water having an alkaline reaction; there is a slight empyreumatic odour evolved." Mr. Buchanan has also mentioned the occurrence of green jasper at the Awatere River (Geol. Rep., 1866–67, p. 35), and Captain Hutton alludes to it near Hongikuri on the Cape Colville Peninsula, where rounded blocks of diorite are encased with a coating of red jasper (Geol. Rep., 1867, p. 8).
Lydian Stone.—A specimen of grey flinty slate from Whangarei is in the collection of the Colonial Museum, and lydian stone is also mentioned by Dr. v. Haast, at the Malvern Hills. (Jurors' Rep. N.Z. Ex., 1865, p. 256.)
Chert and Quartzite are of very frequent occurrence in our metamorphic rocks and silurian beds; they occur as thick beds in the Lower Devonian formation, where they are fossiliferous; are met with again in the Lower Carboniferous and Upper Devonian series; and again in many of the Lower Secondary and Jurassic rocks, where they sometimes occur as fossiliferous beds.
Flint occurs in chalk at Oamaru, in chalk marls at the Kaipara and Bay of Islands, and as black and grey masses in Petrifying Gully, Mt. Somers, where also iron flint of a red and brown colour is found. It is mentioned by Dr. Hector in chalk on Campbell Island (Trans. N.Z. Inst., vol. ii., p. 178), and by Dr. v. Haast as filling cavities in the rocks of Canterbury (Jurors' Rep. N.Z. Ex., 1865, p. 256), and in the limestone of Amuri Bluff, (Geol. Rep., 1870–71, p. 38), and Prof. Liversidge (Trans. N.Z. Inst., vol. x., p. 495) mentions its occurrence at Tapanui, Otago, and Whangarei Heads, Auckland.
Chalcedony.—This mineral has chiefly been found in geodes in the melaphyres and quartz-porphyries of Canterbury, but the specimens are chiefly of an inferior class. They are green, grey, brown, and white, and are sometimes arranged in parallel bands passing into agate or onyx. In the collection of the Colonial Museum, there are specimens from Clent Hills, Gawler Downs, Mt. Somers, and Tokatoka on the Wairoa River. It is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, pp. 266, 437) in the volcanic rocks of Moeraki and Otepopo; by Dr. v. Haast (Jurors'