A significant limitation on the development of zoology, botany and palaeontology in the mid-nineteenth century was the absence of a centralised collection of specimens. Appointed superintendent of the British Museum's natural history departments in 1859, the distinguished biologist Richard Owen (1804-92) quickly realised the need to make various scattered samples more readily available for study, and began campaigning for a new, national museum with unprecedented space and resources. This book is the text of one of his speeches to the Royal Institution, given in 1861 and first published in 1862. He argues against the usual practice of exhibiting only one type form for each genus, provides possible floor plans, and presents case studies across the zoological field which show the limitations of the then current system. He also stresses a new idea, that such a museum should aim not only to help scientists, but to educate the general public.