954 The American Naturalist. [ November, 
At Oufa, at the foot of the Ural Mountains, we entered a zone 
of openly folded paleozoic rocks including the Devonian 
series, the folds becoming rapidly more compressed and the 
disturbances greater as we advanced into the mountains. At 
Slatoust we encountered the first crystalline schists, considered 
by Tschernyscheff our leader, on stratigraphic evidence which 
but few of the party considered conclusive, to be metamorphic 
Devonian. 
Within this band of schists or on its borders, is a group of 
mineral localities which have produced many interesting and 
beautiful specimens obtained by the efforts of many engineers 
of the Russian Mining Bureau through a long series of years, 
and now in large part preserved in the cabinet of the Mining 
Academy in St. Petersburg. These minerals all appear to be 
contact products between clay slates and limestones and mas- 
sive eruptive rocks of the character of diorite or peridotite. 
One of the best known and most typical of these occurrences 
is the Achmatoff mine. Here, on a more or less chloritic 
matrix, were found beautiful crystallizations of garnet, epl- 
dote, pyroxene, vesuvianite, such titamium minerals as perof- 
skite, titanite and ilmenite, zircon, apatite and various mem- 
bers of the chlorite group. 
Passing eastward still across the Ural divide, we entered a 
region of gneisses and granitic rocks. The day spent at 
Miass, in the Ilmen Mountains, under the joint leadership of 
Karpinsky and Arzruni, was replete with interest. The Ilmen 
Mountains are a subordinate range of the Ural chain composed 
largely of eleolite-syenite, classical under Gustav Rose’s name 
of miascite. This rock is well exposed, is rich in a variety of 
minerals and offers numerous interesting problems to the pet- 
rographer. The most notable minerals here collected, chiefly 
from the pegmatitic facies of the rock, were nepheline, can- 
crinite and sodalite, zircon, apatite, ilmenite and biotite 1m 
huge plates. In the pegmatite veins traversing the neighbor- 
ing gneiss and granite, we saw a very different group of mIn- 
erals including albite and microcline, topaz, zircon and euclase 
and samarskite, pyrochlor and other rare earth minerals. 
