Systematic use of trace elements in Igneas processes; Introducción al estudio de los cuerpos igneas; A proposal by the IUGS subcammission on thesystematics of igneas; Rocks for a chimical classiffcation of volcanic rocks based on the total; alkali silica (TAS) diagram; Spilites, Keratophyres, and the igneous spectrum; Classification,characteristics, origin of ophidites; A guide tothe chemical classification of the common volcanic rocks; Volcanic rock series in island are and active continental Margins; Tholeiitic and cole - alkalic series in relation to thebeaviors of; titanium, vanadium,and nickel; Metamorphism - A stdy of the transformations of rock - masses