title: Proceedings: reproduction in the platypus, Ornithorhynchus anatinus, with particular reference to the evolution of viviparity.
mesh_terms: D000818:Animals; D005075:Biological Evolution; D003338:Corpus Luteum / Q000648:ultrastructure; D004622:Embryo, Mammalian / Q000033:anatomy & histology; D004717:Endometrium / Q000648:ultrastructure; D005123:Eye / Q000196:embryology; D005260:Female; D006914:Hydroxysteroids / Q000032:analysis; D008297:Male; D009007:Monotremata / Q000502:physiology*; D006080:Ovarian Follicle; D010063:Ovum / Q000648:ultrastructure; D012098:Reproduction; D013737:Testis / Q000032:analysis
chemical_list: D006914:Hydroxysteroids