1080 The American Naturalist. [December}. 
by six plates containing fifty figures. The intensity of the meta- 
morphism varies widely. At 500 meters from the contact the lime- 
stones are filled with metamorphic minerals, and even at 1.5 kilos from 
the nearest visible contact with the eruptive the limestomes still con- 
tain many of these. The altered sedimentary rocks are limestones, 
calcareous marls and occasionally sandstones. In the limestones the 
principal new minerals found are dipyr, micas, feldspars, tourmaline, 
rutile, sphene, magnetite, hematite, pyrite, apatite, quartz, graphite and 
rarely spinel, epidote and garnet. The calcareous marls have been 
changed to aggregates of silicates with four types of structure, the 
honestone, the micaceous schist and the amphibolitic and dioritic. 
Near the contact the organic coloring matter of the marls has disap- 
peared. A little further away it is changed to graphite and ata 
greater distance it remains intact. The fissures cutting through the 
metamorphic rocks are lined with zeolites, which, however, the author 
does not think are connected in any way with the metamorphic pro- 
cesses. The sandstones, at the only contact seen, were changed into 
quartzites rich in needles of rutile, and a lusite, sillimanite and a few 
flakes of mica. A close similarity exists between the contact action of 
lherzolites and granites. The difference in the two cases consists in a 
corrosion of the metamorphic rocks by the granite and a great produc- 
tion of feldspar, while in the case of the lherzolites there is no transi- 
tion between the metamorphosing and the metamorphosed rocks. The 
conditions determining the nature of the contact rock formed are: 1, 
the original composition of the sedimentary beds; 2, the quantity of 
the volatile and soluble substance accompanying the eruptive; and 3, 
the conditions under which the rock was erupted. 
Nepheline Rocks from the Kola Peninsula.—A full account 
of the nepheline syenite region of the Kola Peninsula, Finland, by 
Ramsey’ and Harkman has recently appeared. The main results of 
the senior author’s study of the region have already been given in these 
notes. Other results can only be referred to, as they are two numer- 
ous to be described in detail. The authors define a new rock t 
imandrite. It is a rock composed of quartz, plagioclase, chlorite, bio- 
tite and several accessory components. The first two minerals occur 
in isometric grains separated from each other by seams of chlorite or 
biotite. The rock has a half clastic structure, since the quartz and 
feldspar appear often as fragments in the interstitial chlorite. The 
quartz is largely secondary, and is supposed to be due to a silicification 
3 Fennia, 11, No. 2, 1894. Also American Naturalist, 1892, p. 334. 
