1894,] Mineralogy and Petrography. 167 
duced in them spinels and augite. The dyke melilite-nepheline-basalt 
near Kemnitz becomes porphyritic around the inclusions. Spinels and 
augite are again the principal new products formed in the granite, but 
in addition to these glass nodules containing chalcedony and tridy- 
mite are also found in the inclusions. On the basalt side of the con- 
tact nepheline is lacking and feldspar takes its place, while the olivine 
of the original rock is broken and corroded. Around a few of the 
inclusions a mineral of the hauyne group has developed. The nephe- 
line-basalt of the Spitzberg near Paulsdorf, contains a very large num- 
ber of included fragments, around which the course of the contact 
processes may be easily studied. Around some of them is an isotropic 
glass containing microlites and trichites, while one large inclusion 
made up of many fragments is discovered under the microscope to 
have its pieces cemented by glass in which are feldspar and quartz 
fragments, and now and then small crystals of augite forming ‘crowns’ 
around the quartzes, besides biotite, granular colorless olivine and crys- 
tals of cordierite, which are always associated with magnetite. As the 
distance from the inclusion increases, the quartz and feldspar gradually 
disappear, augite increases in quantity and olivine of the basalt type 
becomes prominent. The rock then differs from the normal nepheline- 
basalt mainly in containing feldspar and in the absence of nepheline. 
Of course, at a greater distance from the inclusion, the rock assumes 
its normal composition. 
Thermometamorphism around the Shap Granite.—In a 
paper published some two years ago and abstracted in the Bulletin of 
the Geological Society of America‘, Messrs. Harkes and Marr’ dis- 
cussed the interesting effects produced upon andesite and rhyolitic 
lavas and tufas and upon limestones and slates by the intrusion through 
them of a great mass of granite at Shap Fell, in the Lake District, Eng- 
land. The same gentlemen return’ to their study in a late paper, sup- 
plementing and correcting their former statements. They find in addi- 
tion to the andesites and rhyolites, sheets of basalt or of a very basic 
andesite, containing monoclinic and orthorhombic pyroxenes, and like 
the other lavas characterized by an abundance of vesicles filled with 
Products of weathering. These have suffered contact alteration to a 
greater extent than have the primary constituents, though all have 
“Bull. Geol. Soc. Amer., Vol. III, 1892, p. 16, cf. AMERICAN NATURAILST, 
1892 p. 847. 
‘Quart. Jour. Geol. Soc., XLVII, 1891, p- 266.. 
* Quart. Jour. Geol. Soc,, 1893, XLIX, p. 359. 
