376 Proceedings of the Boyal Society 
building stones. Occasionally they are carSonaceotts; or 
they are impregnated, or intermixed, with magnetic 
iron. 
c. Clays, frequently arenaceous or carbonaceous, or both ; 
sometimes ferruginous ; occasionally white and pure. 
They include every variety of kaolin, plastic or potter's, 
pipe, fire, and brick clays ; and ochres or ferruginous 
earths ; many of which are suitable for utilisation in the 
industrial arts. 
d. Shales, also generally arenaceous or carbonaceous, or 
both; sometimes richly fossiliferous, containing espe- 
cially leaves (of exogenous trees and ferns) beautifully 
preserved. 
The coal-beds are frequently directly overlaid or roofed by Newer 
or upper Tertiary strata ; consisting usually of various conglo- 
merates or gravels, sands and clays. 
V. Contained Minerals — 
a. Various Fossil Resins, similar to those which occur in 
the brown coals of G-ermany. To the settlers they are 
generically known as Kauri gum, and are considered 
identical with the fossil resin so called in the North Island 
— which is generally regarded as the produce of the exist- 
ing australis Lambert (N. 0. Coniferce). They 
include Retinite and Ozokerite. 
b. Iron Pyrites (including Marcasite') ; Sulphate of Iron ; 
Clay Ironstone nodules. 
c. Sidphur, generally impregnating sands or sandstones ; 
clays or mudstones. 
d. Quartz, as an impurity. 
e. Jet; and vOgetable debris in the form of Mineral Charcoal. 
VI. Lithological or Physical Characters. — Hand-specimens exhibit 
all gradations between Lignite, Brown Coal, Pitch Coal, Cannel or 
Parrot, and Common British Domestic, Coal. Their texture, fracture, 
and lustre consequently vary extremely. Generally they are earthy 
and massive ; occasionally laminated ; splinter readily on exposure ; 
do not cake in burning; colour and streak, brown to black; specific 
