Advances in the Biosciences 6: Schering Symposium on Intrinsic and Extrinsic Factors in Early Mammalian Development, Venice, April 20 to 23, 1970 is a collection of papers presented at the Schering Symposium on Intrinsic and Extrinsic Factors in Early Mammalian Development, held in Venice, Italy, on April 20-23, 1970. Contributors explore intrinsic and extrinsic mechanisms underlying early development in mammals and cover topics ranging from transmission of maternal proteins into oocytes to normal and abnormal fertilization in mammals; experimental early parthenogenesis in mammals; and nutrient requirements for the culture of preimplantation embryos in vitro. This book is comprised of 33 chapters and begins with an overview of the oocyte and the egg, touching on subjects such as electron microscopy of the primary and secondary oocyte; experimental early parthenogenesis in mammals; and laparoscopic recovery of pre-ovulatory human oocytes after priming of the ovaries with gonadotrophins. The next section is devoted to intrinsic and extrinsic influence on the metabolism of preimplantation embryos and includes chapters dealing with the composition of oviductal and uterine fluids; the role of uterine proteins in embryonic development; sex chromosome markers as indicators in embryonic development; and manipulations of the blastocyst. The remaining chapters examine placental and fetal physiology, immunology and teratology, and differentiation of tissues. This monograph will be of interest to biologists and physiologists.