102 PROCEEDINGS OF THE SAINT LOUIS MEETING 



Discussion 



Answer of author to questions by Dr. W. J. Miller : Regarding the regu- 

 larity in the structure and conformity to walls, I would say that I can not 

 assume that conformity always occurs, but simply state that of 24 recorded 

 cases only one exception was found. New records will be welcome. One 

 should also note whether the irregularity is general or local. 



HYDROUS SILICATE MELTS 

 BY N. L. BO WEN ^ AND G. W. MOREY * 



(Ahstract) 



The system HaO-KaSiOg-SiOa has been studied experimentally by Morey, with 

 careful control and measurement of both temperatures and pressures. His 

 results furnish a basis for the quantitative description of the behavior of the 

 hydrous melts on cooling under various conditions of pressure and illustrate 

 principles of general importance in the consideration of the behavior of mag- 

 mas containing volatile components. 



Read by title in the absence of the authors. 



SIGNIFICANCE OF GLASS-MAKING PROCESSES TO THE PETROLOGIST 

 BY N. L. BO WEN ^ 



(Ahstract) 



Glass-making processes offer little support to the belief in immiscibilty of 

 silicate liquids. They do, however, emphasize that the stage at which the 

 mass is partly liquid and partly solid (crystalline) is of great significance to 

 one interested in the differentiation of igneous rocks. It is principally at this 

 stage that different parts of the melt may acquire composition differences 

 troublesome to the glass-maker, though instructive to the petrologist. 



Read by title in the absence of the author. 



TYPES OF NORTH AMERICAN PALEOZOIC OOLITES 

 BY FRANCIS M. VAN TUYL ^ AND HAROLD F. CROOKS ^ 



(Ahstract) 



Through the cooperation of a number of geologists located in various parts 

 of North America, it has been possible to assemble for study samples from 

 nearly all known oolitic horizons of the Paleozoic. The varieties represented 

 are calcareous, siliceous, phosphatic, and ferruginous. Microscopic study of 

 these shows that they may be classified according to a few important struc- 

 tural types. These are described and the evidence bearing on the probable 

 mode of origin of each is summarized. 



Read bv title in the absence of the author. 



1 Introduced by H. S. Washington. 



2 Introduced by Eliot Blackwelder. 



