Our original conception of the purpose of this book was formulated in the preface to the first Spanish edition, published in 1946 by "EL ATENEO," Buenos Aires:
"This book originally arose from the necessity for a synthesis in the Spanish language of the most important aspects of modern cytology.
"In recent years this branch of biology has shown rapid progress and has become fundamental to the study of the structure and function of living organisms in normal and pathologic conditions. The cell can be regarded as the vital unit of organisms and the anatomic and physiologic substrate of biologic phenomena. In its morphologic aspect, modern cytology has gone beyond simple description of structures visible to the light microscope; by the application of new methods, an analysis has been begun of submicroscopic organization -- the architectural arrangement of the molecules and micelles composing living matter. In its functional aspect, modern cytology has transcended the stage of pure description of physiologic changes, and seeks an explanation of these changes in the intimate physicochemical and metabolic processes of protoplasm. Finally, as a corollary, modern cytology, on the basis of the physicochemical changes of the nuclear structures, has tried to interpret and explain the phenomena of heredity, sex, variation, mutation and evolution of living organisms.
"In the present book, an attempt has been made to stress the morphologic, physiologic and genetic aspects of modern cytology.
One of the most important factors stimulating the progress of cytology has been the development of new methods, in many cases derived . . .