1896.] NEW YORK ACADEMY OF SCIENCES. 29- 



able; the amount of silica varying considerably^ as we would ex- 

 pect from the irregular appearance of quartz. 



Analyses. 



98.86 100.07 99.03 100.13 99.18 



1. Eclogite from Eppenreuth ; by v. Gerichten ; garnet, omphacite, distheue 

 and quartz. 



2. Eclogite from Silberbacli ; by v. Gerichten ; garnet, omphacite, disthene 

 and quartz. 



3. Eclogite from Markt Schorgast ; by v. Gerichten ; garnet, omphacite 

 and hornblende. 



4. Quartz diabase from Przibram, Bohemia, by Dietrich. 



5. Diabase from Fichtelberg, in the Fichteigebirge, by Loretz. 



Nos. 1 and 2 are poor in iron for such basic rocks, but other- 

 wise agree quite closely with diabase (4). No. .3 contains little 

 quartz and is richer in iron than the others, the latter being 

 contained in the garnet. This analvsis compares quite closely 

 with diabase (5). In all these CaO>MgO> Na^O -f K2O. 



It is evident that as far as chemical composition is concerned 

 the eclogite is identical with certain tj^pes of eruptive rocks. 

 Closer comparison of the two is, unfortunately, impossible, ow- 

 ing to the lack of all transition stages and the great mineralog- 

 ical differences, which cannot be fully accounted for in the 

 present state of our knowledge concerning the subject of meta- 

 morphism. 



The Academy then adjourned. J. F. Kemp, 



Secretary. 



Stated Meeting. 



October 26th, 1896. 



The Academy met with Prof. F. H. Giddings in the chair, 

 There were 30 members present. 



