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Nenoliths in these rocks. 
In many respects the xenoliths resemble those of the preceding. 
In a few also olivine was found in large quantities. 
We mention the following combinations: 
1. plagioclase, brown amphibole, hypersthene, augite and magnetite. 
The brown amphibole is invariably resorbed, sometimes completely. 
In the latter case only little hypersthene and augite is present in 
separate crystals, out of the resorption-rims. 
2. plagioclase and light-green amphibole. The amphibole is partially 
resorbed and changed into a mixture of augite and ore. 
3. plagioclase and greenish brown, all but non-resorbed amphibole, 
with little magnetite. 
4. plagioclase, hypersthene, augite, and magnetite. 
>. plagioclase with very little pyroxene. 
6. plagioclase, partially resorbed olivine, hypersthene (and augite), 
little ore and glass. From the enclosing rock vitreous veins intrude 
into the xenoliths. 
IV. The other volcanic products. 
Beyond the above-named rocks, which could be ascribed with 
certainty to a special eruption, a number of rocks were examined, 
the. majority of which will no doubt belong to the products of the 
two latest eruptions, but whose age cannot be established positively. 
In the main they are also hypersthene augite andesites, exceptionally 
amphibole-, and olivine-bearing rocks. Homoeogeneous xenoliths, 
isolated or enclosed by effusive rocks, are numerous; besides these 
we encountered also a few xenoliths of effusive rocks in effusive 
rocks, from which conclusions may be deduced about their relative 
age. 
a. Xenoliths of the hypersthene augite andesites. 
They are in the main medium-grained or porphyr itic holocrystal- 
line rocks; fine-crystalline xenoliths are the exception. 
1. large plagioclase-crystals with enclosed pyroxene, ore and glass. 
2. plagioclase and non-resorbed olivine. 
3. plagioclase, non-resorbed olivine and hypersthene. 
4. plagioclase, augite, hypersthene, brown amphibole, little olivine, 
ore and brown glass with few microlites. 
5. plagioclase, completely resorbed amphibole and very little brown 
glass. The resorption products of the amphibole consist of augite, 
hypersthene, and ore. 
6. fine-crystalline diabases and diabase-porphyrites, consisting of 
