Phylogeny and Classification; The Ovary, Folliculogenesis, and Oogenesis in Teleosts; Modifications in Ovarian and Testicular Morphology Associated with Viviparity in Teleosts; The Testis and Spermatogenesis in Teleosts; Male Reproductive System: Spermatic Duct and Accessory Organs of the Testis; Ultrastructure of Spermatozoa in Agnathans; Ultrastructure of Spermatozoa: Euteleostomi (=Osteichthyes): Cladistia; Ultrastructure of Spermatozoa: Chondrostei; Ultrastructure of Spermatozoa: Neopterygii: Holostei through Osteoglossomorpha; Ultrastructure of Spermatozoa: Elopomorpha and Clupeomorpha; Ultrastructure of Spermatozoa: Ostariophysi; Ultrastructure of Spermatozoa: Euteleostei: Argentiformes, Esociformes, Salmoniformes and Osmeriformes; Neoteleostei: Stenopterygii, Cyclosquamata, Scopelomorpha and Paracanthopterygii; Ultrastructure of Spermatozoa: Acanthopterygii: Mugilomorpha and Atherinomorpha; Ultrastructure of Spermatozoa: Acanthopterygii Continued: Percomorpha; Ultrastructure of Spermatozoa: Sarcopterygii; Sperm Modifications Related to Insemination, with Examples from the Ostariophysi