266 
Farther from the olivine follows a finely crystalline mixture of 
hypersthene (and augite?) with a variable quantity of plagioclase 
and more to the outside also ore; this is succeeded by a zone of 
the larger adjacent plagioclase-crystal, in which pyroxenes are scat- 
tered in an irregular way. 
We see, therefore, that from the magma which yielded these 
xenoliths, first plagioclase and olivine were crystallized, then the olivine 
had lost its stability and a resorption rim of hypersthene was formed, 
enclosed by a margin of hypersthene and ore with very little plagio- — 
clase, while the enclosed hypersthene of the larger plagioclase crystals 
go to show that these crystals continued to form during the erystal- 
lization of the hypersthene. The hypersthene belongs to the last 
erystallization-produets of the xenoliths and they originated partly 
at the cost of olivine. 
b. of the amphibole. Just like the olivine also the amphibole occurs 
entirely unmodified in various xenoliths, especially in the detached 
xenoliths not enclosed by the solid lava. In these xenoliths very 
often rather much glass was found between the crystallized consti- 
tuents. In the olivine-free xenoliths with non-resorbed amphibole 
much magnetite but no or hardly any pyroxene was sometimes 
encountered. The colour varies trom dark-brown to brownish-green 
and dark-, or light-green in the sections with highest absorption ; 
the pleochroism is considerable in the dark-coloured varieties. Gene- 
rally the amphibole is distinctly the last erystallization-produet with 
angular contours relative to the other constituents which are often 
enclosed. 
In the case of faint resorption the resorption-rim consists exclusively 
of a black ore-mass or of a combination of ore, pyroxene and plagio- 
clase. The first case is found e.g. in the amphiboles from the xeno- 
liths that are very rich in this mineral of a brown or greenish- 
brown colour and that do not contain any pyroxene, numerous 
specimens of which occur along the slopes of the voleano. However, 
also in pyroxene-rich xenoliths similar resorption-rims round the 
amphibole are found. In the enclosures from the lava-flow of 1904, 
which contain by the side of amphibole less pyroxene, the ore does 
not only encompass the amphiboles as a rim, but it also penetrates 
along the cleavage-cracks into the central parts of the crystals. The 
resorption-rims, in which besides ore also pyroxene and plagioclase 
occur, were observed in the xenoliths of the eruption-products of 
1914. They are large greenish-brown amphiboles, plagioclase and 
little ore. The plagioclases are sharply defined from the material of 
the resorption-rims, in which the pyroxene consists entirely or chiefly 
