266 The N.Z. Journal of Science and Technology. [Sept. 
To extract the dye from Coprosma areolata a totally different procedure 
is necessary, for contact of the bark with alkalis or iron or mineral acids 
changes the nature of the colour-producing bodies, so that instead of getting 
results similar to those yielded by C. grandifolia only brown colours are 
given to chrome mordants instead of maroon. It is therefore necessary 
to boil the pieces of bark with water several times, when the dye passes 
into the solution, which is now used in the dye-bath. C. areolata bark 
must not be reduced in the mincing-machine or it would thereby come 
into contact with the perforated iron plate and become contaminated 
with iron, which is inimical to the best results. Another peculiarity 
of this species is that by boiling the solution of the bark with dilute 
sulphuric acid a dark-green colour and precipitate is produced, which 
on nearly neutralizing the liquor with soda gives a purplish black on 
wool, fast to soap and light (see specimen No. 3). The water extract 
of this species may be used as a substantive dye (i.e., without any 
mordant) on wool, which it dyes an olive-bronze colour fast to light, 
although as an adjective dye with the mordants mentioned it gives 
better colours. 
Two very common species in Wellington, C. Baueri (the taupata) and 
C. robusta, have given quite negative results in dyeing tests. Coprosma 
lucida, which also has bark and wood of a yellow colour, gives good reddish- 
brown colours, which are fast to light and soap, to chrome and alumina 
mordants. Coprosma foetidissima (the hupiro of the Maori and the “ stink- 
wood ” of the settler), which has a light-green bark, has proved a dis¬ 
appointment, for although giving excellent brown and yellow colours to 
chrome and stannous mordants* respectively, and fast to soap, they are not 
fast to light. This is more to be regretted as the plant has strong tinc¬ 
torial properties and is very abundant in some districts. The difficulty of 
working with a plant having such a powerful and repulsive odour is greater 
than most people would imagine. The best specimens of bark are obtained 
from old trees in the higher forest, at from 1,500 ft. to 2,500 ft. Unfortu¬ 
nately, to get to these habitats tram, train, or boat must be availed of, and 
often the situation of the bark-collector with the other passengers and the 
conductor becomes one of some embarrassment. The name of the genus is 
certainly fully earned by this one disgusting species. The smell is, how¬ 
ever, easily washed out of the dye fabric. The Maori priests are said 
(Treasury of Botany ) to have practised certain rites in order to discover the 
will of the gods by means of hupiro-leaves. A stronger instrument could 
hardly be imagined, albeit, one would think, more suitable to conjure devils 
than gods. 
About a dozen of the commonest or most accessible species growing in 
the vicinity of Wellington have been subjected to preliminary examination 
with regard to the colour of the cortical layers (bark), the reaction which 
they give when treated with a 10-per-cent, caustic-soda solution, and in a 
few cases the capacity of aqueous acid and alkaline extracts for dyeing- 
mordants on wool. From these experiments it appears probable that the 
colour of the cortex and its reaction to alkalis may prove of distinct value 
to botanists in differentiating species of the genus, which, according to 
Cheeseman (Trans. N.Z. Inst., vol. 19, p. 218, 1886), is, next to Veronica, 
the most puzzling in the New Zealand flora. 
* Molybdenum used as a mordant, however, shows signs of giving faster colours 
with this species. 
