PETROLOGICAL ABSTRACTS AND REVIEWS 489 



methods has been condensed as much as possible, smce this data is given else- 

 where. The alphabetical list of minerals has been much extended, and is now- 

 placed at the back of the book in such a position that it may be consulted 

 without turning pages. Finally, a short section on the classification of igneous 

 rocks according to the author's system has been added. As given here, this 

 classification is essentially the same as that published in the Journal of Geology 

 several years ago, except that the whole of the monzonitic series, with the 

 exception of monzonite and quartz-monzonite, has been omitted. 



Kaiser, Erich. ''Der Elaolithsyenitlakliolith der Serra de Mon- 

 chique im siidlichen Portugal," Neues Jahrh., B.B., XXXIX 

 (1914), 225-67, pis. 2, profiles 2, map i, figs. 6. 



Discusses the structure of the Serra de Monchique in southern Portugal, 

 with special reference to the nephelite-syenite central mass. He considers this 

 a laccolith that was intruded during the period of folding. The main foyaitic 

 mass with border pulaskites, and various dike-rocks are briefly described. 



Kaiser, Erich, "tjber ein Demonstrationsmikroskop fiir den 

 mineralogischen und petrographischen Unterricht," Zeitschr. 

 f. KrysL, LIII (1914), 397-403- 

 Describes a microscope for demonstration purposes. It has a large, rotat- 

 able stage with ten openings, so that that number of thin sections can be placed 

 on it at one time, and the specimens observed one after the other. A glass 

 plate prevents the disturbance of the sections by students. Since the prepara- 

 tions cannot be turned there is provided a means for rotating the tube of the 

 microscope. 



Kaiser, Erich. " Studien wahrend des Krieges in Siidwestafrika," 

 Zeitschr. d. deutsch. geol. Gesell., LXXII (1920), 50-76. 

 The three studies included in these papers are: (i) Assimilationsercshein- 

 ungen an den Elaeohthsyeniten des Granitberg in siidKchen Namib," (2) "Zur 

 Kenntnis der HohKormen, Eindeckungen, Ausfiillungen und Aufschiittungen 

 der Trockengebiete," and (3) "Kalkkrusten." In the first paper the nephe- 

 lite-syenite stock of Granitberg, in southern Namib, is described. Besides the 

 normal rock there are certain other types which cannot be explained by normal 

 differentiation. The contact of the main mass is irregular and blurred, owing 

 to the penetration of the country rock by numerous veins and apophyses of 

 the igneous rock, thus giving the impression of an irregular breccia penetrated 

 by the nephelite-syenite. But it is not a breccia in the ordinary sense since 

 the fracturing was caused by the intrusion itseK. Both intrusive and intruded 



