Molecular Cytogenetics -- Genetics of Heterochromatin in Drosophila and Maize -- Chromosome Accomodation to Integration of Foreign DNA -- Rapidly Evolving Bkm DNA is Associated with Hypervariable Domains -- Chromosomes of Drosophila -- Molecular Dissection of the Drosophila Chromosome -- Polytene Chromosomes of Drosophila -- Structure and Function of Y Chromosomal Genes in Drosophila -- Chromosomes and Evolution -- A Model for Heterochromatin Dispersion and the Evolution of C-Band Patterns -- The Role of Chromosomes in Speciation: A new Interpretation -- Chromosome Evolution in Marsupials -- Comparative gene Mapping and Primate Evolution -- Chromosomes and Malignant Changes -- Chromosomal Abnormalities in Malignant Lymphoid cell Proliferations. Recent Advances -- Retroviruses with two Oncogenes -- PH1 Chromosome: Cytogenetics and Molecular Aspects -- Sex Chromosomes -- Conservation in toto of the Mammalian X-Linkage Group as A Frozen Accident -- The Genetic Basis of Testis Determination in Man -- A Molecular Analysis of the Human Y Chromosome -- An Evolutionaryly Conserved Early Replicating Segment on the sex Chromosomes of Man and the Great Apes -- Meiosis and Aneuploidy -- Meiotic Behavior of Sex Chromosomes; what is Normal? -- DNAse I Hypersensitivity Characterizes the XY Pairing Region at Meiosis in Man -- Chromosome Behaviour at Female Meiosis in two Murine (Robertsonian) Trisomies -- Meiotic Chromosome Pairing in the Human Male. Experience from Surface Spread Synaptonemal Complexes -- The Oocyte Spindle and Predisposition to Aneuploidy in Mice -- Nucleolus Organiser -- The Molecular Organization of the Human Ribo-Somal Gene -- Nucleolus Organizer Regions and Nucleoli: Cytological Findings -- Relations Between Nucleoli and Nucleolus-Organizing Regions During the cell Cycle -- Nucleolar Organisers in Plants -- Immunocytochemical Localization of RNA Poly-Merase I in the Fibrillar Centers of Nucleoli -- Distribution of Rdna and of Its Transcription Sites in the Nucleolus of the Human Sertoli cell -- Association of Ribosomal Genes in the Human Oocyte At Meiotic Prophase. Cytogenetic Consequences