Correspondence. 315 
been presented during the current year. It is a careful and detailed 
study of the geology of a limited district in the vicinity of Bergen, 
Norway. The geology in general has an Archasan aspect. The bedded 
rocks stand vertically, though in places much disturbed, and they 
embrace many varieties of crystalline schists and gneisses, associated 
with diorites, diorite-schists, gabbros and other forms of tufts and 
eruptives. The features of chief interest, however, are conglomeritic 
gneisses, and fossiliferous phyllites and limestones interstratified with 
the gneisses and crystalline schists. 
These phenomena were studied especially at three separate points, 
Osoren, Trengereid, and the mountain Ulriken. In the environs of 
06()ren are described the following petrographic forms : 
1. Quartziferous talc-mica schist; the quartz occurring partly in 
very small and thin lenses, and partly in larger ones, attaining occa- 
sionally a metre in length. This rock contains also layers of a finely 
granulated gray gneiss with very little mica. 
2. Diorite schists in two zones, a northern and a southern. Both 
are associated with hornblende schist, chlorite schist, gneiss often 
rich in chlorite, granulite and green slates. The latter are sometimes 
so closely intersected by fine granite and granulite veins as to present 
the appearance of a breccia. In this connection is a rock consisting 
either almost entirely of coarsely crystalline hornblende or of large 
hornblende crystals up to a centimetre in size, scattered in a mass of 
fine hornblende crystals. In the granulite occur lenses of granular 
quartz. The hornblend ' schist is laminated by films of chlorite, and 
contains flat lenses of finely granulated feldspar varying from the 
thickness of paper to that of pasteboard. 
3. Polygenous conglomerate, of which the constituent pebbles have 
been compressed until they assume in places the forms of thin lenses. 
Their longest dimension is in the plane of bedding, and in the direction 
of the strike. The least is transverse to the bedding. This rock some- 
times presents a crumpled appearance. Mica and chlorite often appear 
in such a manner as to prove them epigenetic. Where the conglomer- 
ate has been subjected to extraordinary pressure and mica is in 
abundance, its appearance is similar to that of mica schist ; but where 
hornblende is in excess, it has the appearance of hornblende schist. 
These conglomerate beds are in alternation with gray gneiss, black 
micaceous phyllite and "eye-gneiss." 
4. The "Osgneiss" (Augen-gneiss, eye gneiss) unlike the proper 
Augen-gneiss of the Germans, has "eyes" of whitish quartz in the 
midst of obscurely stratified feldspathic rock. The feldspar contains 
lamina^ of chlorite which in some places is substituted by black mica. 
5. Phyllites. These occur in two similar zones, both of which con- 
tain fossils. Accessories of dull or black mica cause incomplete trans- 
itions to mica schist, and thence to perfect muscovite schist. Tiie 
phyllites contain occasional beds of fine granular gneiss ; also distinct 
layers of limestone and small balls of dark colored limestone, with fos- 
sils changed into calcareous spar. The fossils recognized are Halt/sites 
